Call Barring Not Working: What Each Error Message Means and How to Fix It

You tried to turn call barring on or off, and instead of the usual confirmation you got an error: "Connection problem or invalid MMI code," "Network or SIM card error," or the switch just refused to move. None of these messages names the actual cause. This guide goes through what each one really means, why the same message covers several different problems, what to check on your own phone before you call your carrier, and what to do if all you want is to stop your own outgoing calls.

If you called someone and were told their line is barred, that's a different situation, covered in Call Barred Meaning. If you just need the steps to turn call barring on or off, see What Is Call Barring?

Current as of October 2026. Error wording is confirmed against Android's public source code (AOSP), which Pixel and other stock-Android phones run close to. Samsung uses its own Phone app, so its exact wording can differ; where we couldn't confirm Samsung's own text, this guide says so.

1. The short answer

Android's call barring error messages do not name a cause. The two you'll see most often, "Connection problem or invalid MMI code" and "Network or SIM card error," are catch-all messages: Android's own source code uses each one for several unrelated situations, from a mistyped code to your carrier flatly refusing the request. Seeing one of them does not, on its own, tell you whether your SIM is faulty, your password is wrong, or your carrier simply does not let you control call barring from the phone.

2. What each error message actually means

These meanings come from Android's own open-source code (AOSP), which Pixel and other phones using the stock Google Phone app run close to. Samsung uses its own Phone app, and Samsung has not published how it maps carrier responses to on-screen text, so treat the Samsung notes below as likely, not confirmed.

"Connection problem or invalid MMI code"

This appears when you dial a code like *33*PW# directly in the Phone app's dialer. Android's handling of these codes (GsmMmiCode, and its VoLTE equivalent ImsPhoneMmiCode) shows this one generic message for three different situations: the code's format wasn't recognized, your carrier rejected the request for a reason that doesn't have its own message, or the connection failed before a response came back. What it is not, in standard Android, is the message for a wrong password — a wrong password gets its own separate message, "Incorrect password" (next). Check section 4 before you touch the password at all.

"Call barring / Incorrect password"

Also appears from the dialer. With *33-style codes, this is the message Android shows when your carrier reports a wrong call barring password, on both regular and VoLTE connections. The phone also shows it on its own when you change the password with **03*330* and type the new password differently the two times. If you see it after a *33-style code, the password really is the issue. Try the default your carrier publishes once (see Call Barring Codes), then stop and contact your carrier instead of guessing again — too many wrong attempts in a row can lock the service until your carrier resets it.

"Network or SIM card error"

This one appears on the Call barring settings screen, not the dialer, under a dialog Android itself titles "Call settings error." It's the generic message for carrier refusals that don't have dedicated text of their own, including a wrong password, which, unlike in the dialer, gets no message of its own here. (A Fixed Dialing Numbers conflict has its own message, and a request that comes back as not supported shows no message at all; both are covered below.) When it shows up, the setting you were changing turns grey, meaning the request failed; that is not a diagnosis of your SIM. Despite the wording, it does not mean your SIM card is damaged.

"Unexpected response from network"

Also on the settings screen. Here your carrier did reply, but the content of the reply was empty or couldn't be parsed — Android treats this differently from an outright refusal, so the setting often stays available for you to try again, although it can still turn grey (for example, when the reply came back empty). If this keeps happening, move somewhere with a stronger signal and retry before contacting your carrier.

"Feature not supported" / a switch that's simply greyed out with no message

These are the same answer seen in two places. When you dial a code and the reply is that the operation isn't supported, Android shows "Feature not supported." On the settings screen, the same "not supported" reply produces no message at all: Android simply greys out the row. Either way, the request was refused as unsupported, which isn't something you can fix from the phone; ask your carrier whether call barring is available on your line.

"Operation is restricted to fixed dialing numbers only"

This message, and its settings-screen version explaining that "some call-related features aren't working" because of your Fixed Dialing Numbers setting, means Fixed Dialing Numbers (FDN) — the SIM's own allow-list of numbers it can call — is turned on, and it is blocking the barring request itself, not only ordinary calls. Turn FDN off first (section 4), then try call barring again.

"Call barring rejected" and other carrier-worded messages

Some phones and some carrier responses use wording like "call barring rejected" or "request rejected" that doesn't come from Android's own open-source code. It's likely added by the phone maker or passed through from the carrier, and we couldn't confirm exactly where it originates. What the mobile standard does describe is a carrier's right to deny a subscriber's own request to change barring when the line is managed by the carrier — covered in section 6. In practice, if you see "rejected," assume your carrier is the one declining the request and go straight to section 6's advice on what to tell support.

3. Call barring not showing in settings

Android hides the Call barring entry entirely unless your carrier switches on a configuration flag for it, and that flag is off by default. A missing menu is the normal starting state, not a sign your Phone app is broken. Separate carrier settings in standard Android can also hide just the "Change password" or "Deactivate all" options while leaving the rest visible, so a half-missing menu can be normal too.

On a Samsung Galaxy, the equivalent sits a level deeper: Phone → ⋮ → Settings → Supplementary services → Call barring → Voice call. Depending on the model and the carrier, that menu may not appear either.

The menu and the dialer codes are controlled separately: a code like *33*PW# goes straight to your carrier regardless of what the settings screen shows, which is why the codes sometimes work even with no "Call barring" row to tap. That isn't guaranteed, though — if your carrier doesn't support call barring at all, the codes fail too, with "invalid MMI code" or "Feature not supported." Full code list, how they're built and the password: Call Barring Codes.

One more reason people land on this page: Google's own Phone app help article, "Block or unblock a phone number," is about rejecting incoming calls from a specific number — it has nothing to do with the carrier's call barring service. If that's the page you found while searching, you likely want Call Barred Meaning or What Is Call Barring? instead, depending on what you're trying to do.

4. Checks to do before calling your carrier

Work through these roughly in order. Any one of them can produce the exact same "invalid MMI code" or "Network or SIM card error" message, so ruling them out first saves a call.

Pick the right SIM

On a dual-SIM phone, call barring and its password are set per SIM. Check that the SIM selected in the Call barring menu, or the line the code is being dialed on, is actually the one you mean to change.

Mobile data (and data roaming) on

Some carriers only accept call barring changes over a data connection to the carrier's own systems rather than over the voice network, and Android has a dedicated warning for exactly this: "To use Call barring, make sure mobile data is turned on," with a data-roaming version for use abroad. On a dual-SIM phone it names the SIM: "…make sure mobile data is turned on for SIM 2." On a Pixel we tested, the Call barring screen refused to open at all until mobile data for that SIM was switched on.

Airplane mode off, signal on

If the phone's radio is off, for example in airplane mode, Android shows "Turn on the radio before viewing these settings" instead of letting the menu open at all. Confirm airplane mode is off and you have signal before trying again.

Fixed Dialing Numbers off

FDN blocks more than ordinary calls — Android's own message says turning it on makes "some call-related features" fail, and call barring is one of them. If you don't use FDN, confirm it's off; if you do use it for another reason, turning it off just to test tells you whether it was the cause.

Turn off call forwarding first

The standard refuses to let you turn on "bar all incoming calls" or "bar all outgoing calls" while related calls are being forwarded, and it describes the same kind of conflict running the other way too. Vodafone Australia's own call barring support page tells customers using these codes to "dial ##002# first," which clears every call forwarding setting before barring is touched. If you have any forwarding active, clear it, set barring, then turn forwarding back on if you need it.

Type the code exactly

The codes are built from exact characters — an asterisk, a service code, an asterisk, the password, a hash — and a single wrong character anywhere in that string produces the same generic "invalid MMI code" message as an actual refusal. Retype it in the Phone app's own dialer rather than pasting it from somewhere else.

Try the password once, then stop

If everything above checks out and you're confident this is a password issue, try your carrier's published default once (the known examples are in Call Barring Codes). Under the standard, more than three wrong attempts in a row make every password-related request impossible until your carrier tells its network to accept them again, so repeated guessing only makes the eventual call to your carrier longer.

5. By phone maker: where the setting is and what to watch for

The paths below come from each maker's own support pages or from carriers' model-by-model guides. They change with the maker's software version, the Android version and the carrier, and the entry only shows up at all if your carrier has turned it on (section 3), so use them as a map of where to look rather than a promise of what you'll see.

Samsung Galaxy

Samsung puts call barring inside Phone → ⋮ → Settings → Supplementary services → Call barring → Voice call. On current One UI versions, Voice call and Video call are separate items, each with its own switches, and both use the same password, because the standard defines one barring password per subscriber for all barring services. Samsung India's troubleshooting page for calls that won't connect lists call barring as one of the possible causes, and says that if it is on, you should contact your SIM's carrier to deactivate it. Samsung US's page on Galaxy calling features doesn't cover call barring; for the features it does describe, it says "Availability may vary by carrier and phone model." For the full Galaxy walkthrough, codes and Fixed Dialing Numbers, see Block Outgoing Calls on Samsung.

Google Pixel, and other phones using Google's Phone app

Google's own Phone app and Pixel help pages don't document call barring, and none of the carrier model guides we checked covers a Pixel, so we can't show a Pixel-specific screen. What is documented is the path on other phones that run Google's Phone app — Motorola, TCL, HONOR, the Redmi A3, and vivo models using "Google Dialer": Phone → ⋮ → Settings → Calling accounts → your SIM → Call barring. On some phones the step is called Calls instead of Calling accounts. The screen itself is standard Android, which lists All outgoing, Outgoing international, Outgoing international roaming, All incoming and Incoming international roaming, plus Deactivate all and Change password.

Xiaomi and Redmi

Vodafone UK's guides show two layouts. Phones with Xiaomi's own Phone app, such as the Xiaomi 12 Pro and Redmi Note 10 5G (Android 11–12), use Phone → ⋮ → Settings → Calling accounts → Advanced settings → Call barring; on dual-SIM models you then pick the SIM. Phones that ship with Google's Phone app, such as the Redmi A3 (Android 14), follow the Google path above instead. If you can't find Advanced settings, check which Phone app your model uses.

OPPO

On current OPPO models — the A6 Pro 5G and Find X9 Ultra on Android 16, and the A5 5G on Android 15 — carrier guides show Phone → ⋮ → Settings → Calling accounts → Operator-related settings → Call barring. On older models such as the A54s (Android 11), the same entry is labelled Carrier call settings, and the SIM is chosen after tapping Call barring. Either way, the menu's name is a reminder that what's inside comes from your carrier.

vivo

vivo's support pages give two paths: with vivo's own dialer, Phone → ⋮ → Phone settings (Call settings on some versions) → Call barring; with Google Dialer, Phone → ⋮ → Settings → Calling account → your SIM → Call barring (one vivo answer labels it Call restriction). vivo's answer to "Why can I not enable Call barring" is that these services are provided by the carrier, so check with your SIM's carrier that the service is enabled. vivo also says that if you forget the call barring password, the carrier is the one to change it.

Motorola

For the Moto G04 (Android 14), both Vodafone UK and Telstra show Phone → ⋮ → Settings → Calling accounts → your SIM → Call barring, then the barring type, the password and TURN ON. Vodafone Australia's Moto G14 guide uses Settings → Calls → Call barring instead, so look for either name.

HONOR

For the HONOR 400 and Magic7 Pro (Android 15), Vodafone UK shows Phone → ⋮ → Settings → Calling accounts → your SIM → More → Call barring. The extra More step is the one most likely to be missed.

TECNO

Carlcare, the official service brand for TECNO, Infinix and itel phones, lists call barring among the causes of incoming calls showing as busy. Its TECNO CAMON 12 steps are Phone → ⋮ → Settings → Calling Accounts → your network → Call Barring, then check that no barring is on, or tap Deactivate All and enter the password.

6. When only your carrier can fix it

Some of the messages above aren't something you can work around from the phone, because of how the mobile standard itself defines call barring.

Your carrier controls barring on your line

When a line is set up as controlled by the carrier rather than by the subscriber, the standard says a subscriber's own attempt to activate or deactivate barring, or to register a password, "will be denied." No error message distinguishes this from an ordinary failure; the request is simply refused.

Your carrier does not offer it to subscribers

Separately, the standard allows a carrier not to offer self-managed barring at all: A service provider needs not offer the option "control of barring services" to his subscribers. If your carrier's help pages never mention call barring, this is a likely reason, and it's worth confirming with support before spending more time on the codes.

Roaming abroad

Outside your home network, the foreign network may not support call barring: UK carrier EE's own guidance says "Not all foreign networks support call barring." The standard also describes one specific case: if you have barred international calls except those to your home country and you roam onto a network that doesn't support that type of barring, a status check comes back as "not supported." If you're trying to set this up while already travelling, checking before you leave avoids the ambiguity.

What to tell the support agent

Ask specifically for "call barring" or "the network password for call barring" — those exact words help avoid the agent starting the unrelated SIM PIN or PUK process instead. Tell them the exact message your phone showed, and mention you've already checked mobile data, airplane mode, Fixed Dialing Numbers and call forwarding, which rules out most of what support would otherwise ask first.

In the US, Verizon's international calling FAQ tells customers to call 611 to block all international calls, and doesn't list a *33-style code for it. In India, Jio's FAQ "Which are the different call management services offered by Jio?" lists caller ID (CLIP), call waiting, call hold and call forwarding, but not call barring — so if your carrier's equivalent page is similarly silent on it, that's consistent with the feature simply not being offered on your plan.

7. If you only want to stop your own calls

Call barring is a carrier feature: it needs your carrier to support it, a password only your carrier controls, and a live round trip to the carrier's network every time you change it. None of that is really about the thing most people are actually trying to do, which is stop certain calls from going out at all.

If that's the real goal, NoDial is an Android app that blocks outgoing calls on the phone itself, without touching your carrier's settings or password. You choose which numbers, calls to every country except the ones you allow, or every outgoing call. For specific numbers and for all outgoing calls, you also choose how: always, on set days and hours, or up to a limited number of calls per day, week or month; the international block is simply on or off. Unblocking a specific number takes effect an hour after you ask, so a number you blocked on purpose can't be unblocked in the moment (turning off the all-calls or international block is immediate); emergency numbers can never be added to the list; and it works the same way no matter which carrier you're on. NoDial does not touch incoming calls — it only blocks the calls you make.

For the options side by side: How to Block Outgoing Calls to a Specific Number on Android, How to Block International Calls on Android, and How to Block All Outgoing Calls on Android.

8. FAQ

Why is call barring not working on my phone?

Usually one of: the wrong SIM is selected, mobile data is off, airplane mode is on, Fixed Dialing Numbers is on, call forwarding is on, the code was mistyped, the password is wrong, or your carrier doesn't support it or controls the line itself. The on-screen message usually doesn't say which, so check them in that order: the things on your phone first, your carrier last.

What does "network or SIM card error" mean for call barring?

It's Android's catch-all message on the Call barring settings screen for carrier refusals that have no message of their own. It also appears for a wrong password, so it does not mean your SIM card is damaged.

Does "invalid MMI code" mean my call barring password is wrong?

Not necessarily. With *33-style codes, standard Android shows a separate message, "Incorrect password," when your carrier reports a wrong password. "Invalid MMI code" can mean a mistyped code, a request your carrier refused, or a failed connection.

What does "unexpected response from network" mean?

Your carrier replied, but the reply was empty or Android couldn't read it. Try again with a stronger signal; if it keeps happening, contact your carrier.

Why is call barring not showing in my settings?

Android hides the Call barring menu unless your carrier turns it on, and the default is off. On Samsung it's under Supplementary services; on phones using Google's Phone app it's under Settings → Calling accounts → your SIM; on recent OPPO models, under Calling accounts → Operator-related settings. The dialer codes sometimes still work even when the menu is missing, though not if your carrier doesn't support barring at all.

Why does call barring get rejected?

Often because your carrier controls or does not offer self-service barring on that line, call forwarding is active, or the password is locked after too many wrong attempts. Most of these can only be fixed by your carrier.

Can call forwarding stop call barring from turning on?

Yes. The standard blocks turning on an outgoing or incoming bar while related calls are being forwarded. Clearing forwarding first (dial ##002# to clear all of it, per Vodafone Australia's guidance) is one way around the conflict.

Is there a way to stop my own outgoing calls without call barring?

Yes. An app that blocks outgoing calls on the phone itself, such as NoDial, doesn't need your carrier's support or password. It only affects calls you make; it does not block incoming calls.

9. Summary

• "Invalid MMI code" and "Network or SIM card error" are catch-all messages, not diagnoses.
• Standard Android reports a wrong password as a separate, specific message in the dialer.
• Call forwarding, Fixed Dialing Numbers, mobile data and SIM selection can all produce the same generic errors.
• A missing Call barring menu is normal: it's off by default until your carrier enables it.
• Some refusals — a carrier-controlled line, a carrier that doesn't offer self-service barring, unsupported roaming — can only be fixed by your carrier.
• To stop only your own calls, without a carrier or a password, use NoDial instead.

NoDial: block calls to the numbers you choseNo barring password, no carrier call.

Sources

• AOSP, frameworks/base core/res/res/values/strings.xml (mmiError, mmiErrorNotSupported, mmiFdnError strings) and GsmMmiCode.java (getErrorMessage, PASSWORD_INCORRECT handling) android.googlesource.com / android.googlesource.com
• AOSP, ImsPhoneMmiCode.java (same error handling for VoLTE connections) android.googlesource.com
• AOSP, packages/services/Telephony res/values/strings.xml (exception_error, response_error, fdn_check_failure, radio_off_error, supp_service_over_ut_precautions, supp_service_over_ut_precautions_dual_sim) and TimeConsumingPreferenceActivity.java / CallBarringEditPreference.java (onException: REQUEST_NOT_SUPPORTED greys out the row without a dialog; an empty reply greys it out with response_error) android.googlesource.com / android.googlesource.com
• Android Developers, CarrierConfigManager (KEY_CALL_BARRING_VISIBILITY_BOOL defaults to disabled) developer.android.com
• AOSP, frameworks/base CarrierConfigManager.java (KEY_CALL_BARRING_OVER_UT_WARNING_BOOL; KEY_CALL_BARRING_SUPPORTS_PASSWORD_CHANGE_BOOL and KEY_CALL_BARRING_SUPPORTS_DEACTIVATE_ALL_BOOL) android.googlesource.com
• 3GPP TS 22.088 (ARIB copy), "Call Barring (CB) Supplementary Services" (carrier-controlled lines: an attempt to activate, deactivate or register a password "will be denied"; A service provider needs not offer the option "control of barring services" to his subscribers.; one password per subscriber for all barring services; §1.3.11: when roaming on a network that does not support barring of international calls except to the home country, a status check returns "not supported") arib.or.jp (PDF)
• 3GPP TS 22.082 (ARIB copy), "Call Forwarding (CF) Supplementary Services" (barring an outgoing/incoming category is refused while related calls are being forwarded, and vice versa) arib.or.jp (PDF)
• 3GPP TS 22.004 (ARIB copy), "General on supplementary services" (after more than three consecutive wrong passwords, every password-related request is made impossible until the carrier tells the network to accept them again) arib.or.jp (PDF)
• 3GPP TS 24.080 (ARIB copy), "Mobile radio interface layer 3 supplementary services specification" (carrier-returned refusal reasons, including negativePasswordCheck, numberOfPW-AttemptsViolation, ss-SubscriptionViolation and ss-NotAvailable) arib.or.jp (PDF)
• 3GPP TS 22.030 (ARIB copy), "Man-Machine Interface (MMI) of the User Equipment" (call barring code format) arib.or.jp (PDF)
• Vodafone Australia, call barring support page ("If you're using GSM codes to restrict incoming or outgoing calls, dial ##002# first") vodafone.com.au
• EE, "Manage call barring to block or unblock calls" ("Not all foreign networks support call barring") ee.co.uk
• Verizon, "International Long Distance FAQs" ("To block all international calls, call 611"; no dial code listed) verizon.com
• Jio, "Which are the different call management services offered by Jio?" (lists CLIP, call wait, call hold and call forwarding; call barring is not listed) jio.com
• Samsung India, "Why the calls are not getting connected" (lists call barring among the causes of calls not connecting; if it is on, contact the SIM service provider to deactivate it) samsung.com
• Samsung US, "Calling features on your Galaxy phone" ("Availability may vary by carrier and phone model."; the page does not cover call barring) samsung.com
• TechBone, "Samsung Call Barring: Turn On or Off" (Voice call and Video call as separate categories with their own switches) techbone.net
• Google, "Block or unblock a phone number" (Phone app help for incoming-number blocking, not call barring) support.google.com
• AOSP, packages/services/Telephony res/xml/gsm_umts_call_options.xml and res/values/strings.xml (labelCallBarring "Call barring", call_barring_baoc / baoic / baoicr / baic / baicr, call_barring_deactivate_all, call_barring_change_pwd) android.googlesource.com / android.googlesource.com
• vivo, Phone FAQs ("How to enable or disable call barring?", "What if I cannot set call barring?", "Why can I not enable Call barring, Call waiting or Call forwarding?", "What should I do if I forget the call barring password?") vivo.com
• Vodafone UK device guides, "Turn call barring on or off": Xiaomi Redmi A3, Xiaomi 12 Pro, Xiaomi Redmi Note 10 5G, OPPO Find X9 Ultra 5G, OPPO A54s, Motorola Moto G04, HONOR 400, TCL 60R 5G Redmi A3 / Xiaomi 12 Pro / Redmi Note 10 5G / OPPO Find X9 Ultra / OPPO A54s / Moto G04 / HONOR 400 / TCL 60R
• Telstra, "Turn call barring on your OPPO A5 5G Android 15 on or off" telstra.com.au
• Vodafone Australia, "Guide for the Motorola Moto G14 - Turn call barring on or off" vodafone.com.au
• Carlcare (official service for TECNO, Infinix and itel), "How To Fix TECNO CAMON 12 incoming call busy problem" (turning off call barring under Calling Accounts) carlcare.com

Menu names, default passwords and which services are offered vary by phone maker, Android version and carrier. Check your carrier's own help pages if a step does not match what you see.