Why the number is not blocked in the blacklist on Android Xiaomi – a full analysis of the causes and solutions

You’ve added a pesky number to the blacklist on Xiaomi’s smartphone, but calls and SMS keep coming in? The problem is familiar to many owners of devices based on MIUI – from the budget Redmi Note to the flagship Xiaomi 14. In this article, we’ll take a closer look at why the lock feature may not work, even if you’re sure you did everything right.

The bugs are not only software bugs (although they are common), but also the implementation of the blacklist in the MIUI firmware. For example, some users are unaware that there are two independent blacklists on Xiaomi, the standard Phone app and the Security service, and the synchronization between them does not always work correctly, and the problem may lie in operator settings, application conflicts, or even in the hardware limitations of the modem chip.

We've collected all the possible causes, from obvious to exotic, and we'll offer workable solutions for each, and at the end of this article, you'll find an FAQ with answers to frequent questions and a checklist for quick diagnosis of the problem.

1.Two blacklists: why the number is blocked in the wrong place

The most common mistake Xiaomi users make is to add a number to the wrong blacklist, and there are actually two in MIUI firmware:

• 📱 Local blacklist – in the standard “Phone” app (Contacts) → Blacklist, blocking calls and SMS device-level.
• 🛡️ Cloud blacklist – in the Security app (Security) → Blacklisted Syncs with Mi Account and can block numbers on all your Xiaomi devices.

If you add a number to just one of these places, it may continue to bother you, for example, a cloud list sometimes ignores SMS, and a local one does not block VoIP (WhatsApp, Viber) calls.

How to check:

1. Open Phone → Contacts → Blacklist and make sure the number is on the list.
2. Then go to Security → Blacklist and check there.
3. If the number is not in one of the places, add it there.

⚠️ Warning: After adding a number to both lists, restart your smartphone. MIUI (especially 12-14) require rebooting to apply changes.

2. MIUI firmware bugs: known problems and workarounds

MIUI is famous for its features, but it also has bugs, and some versions have critical errors in the call lock module.

• 🐛 V MIUI 12.5–13 on the Redmi Note 10/11 and POCO X3 There was a bug that caused the blacklist to be reset after the Phone app update».
• 🔄 V MIUI 14 (Android 13) on Xiaomi 12T redmi K50 The numbers were blocked only partially - calls were missed, and SMS no.
• 📶 On some dual-SIM devices (e.g, POCO F4) The blacklist only worked for the main SIM-map.

How to fix it:

1. Update your firmware. Go to Settings → About Phone → Update your system and install the latest version of MIUI.
2. Clear the app cache.

Settings → Applications → Application Management → Phone → Storage → Clear cache


Settings → Applications → Application Management → Security → Storage → Clear cache

1. Reset your network settings. Sometimes it helps with dual-SIM problems:

→ SIM-maps and mobile networks → Network reset

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If the problem persists after the update, try to roll back to the previous version of MIUI via Settings → About Phone → MIUI Version → Three-Point Badge → Select an update package. Download stable firmware from the official Xiaomi website.

3. Conflict with third-party applications

If you use alternative calling apps (like Truecaller, Google Phone) or instant messengers (WhatsApp, Telegram), they can intercept the lock before the system blacklist works, especially for:

• 📞 Truecaller has its own blacklist that can conflict with the MIUI.
• 💬 WhatsApp/Telegram — Block only messages in the app itself, but not VoIP calls.
• 🔒 Some antiviruses (e.g. Avast, Kaspersky) have call blocking modules.

Decision:

1. Open the conflicting app settings and turn off its blacklist.
2. For Truecaller:

Truecaller → Settings → Block → Disable number lock

1. For messengers, check the notification and lock settings:

WhatsApp → ⚙️ → Notifications → Calls → Allow notifications (turn off if you need to block)

⚠️ Note: If you use Google Phone instead of Xiaomi’s standard Phone app, blacklist MIUI If this is the case, block the numbers directly on Google Phone.

4.Problems with SIM-card-carrier

Sometimes the reason is not the smartphone, but the operator’s settings. Some mobile networks (for example, MTS, Beeline in Russia or Jio in India) use their own locking services, which can conflict with MIUI.

• 📶 Roaming – in roaming, the operator can ignore local lock settings.
• 🔄 Dual-SIM – if the number is added to the blacklist for one SIM, He can call the other one.
• 📡 VoLTE/VoWiFi — call-in 4G/5G Wi-Fi sometimes bypasses a standard lock.

What to do:

1. Call the operator and check whether he supports service locking numbers (for example, MTS service is "Black list").
2. If you use dual-SIM, add a number to the blacklist for each SIM separately.
3. Turn off VoLTE (if not critical):

Settings → SIM- Maps and Mobile Networks → [Select SIM] → Calls → VoLTE → Disable

5. Hidden settings and developer modes

MIUI has hidden options that can affect blacklisting, such as when you're in developer mode, you can turn off background optimization, which sometimes helps with blocking bugs.

How to turn on the developer mode:

Settings → The phone. → Version. MIUI → Stick 7 times on the inscription "Version" MIUI"

What settings to check:

• 🔧 Limitation of background processes:

Settings → Additional → For developers → Background Process Limit → Standard Limit

• 📱 Optimization MIUI:

Settings → Additional → For developers → Optimization MIUI → Include

• 🔒 Permissions for the telephone application»:

Settings → Applications → Application Management → Phone → Permissions → Enable All

6. Hardware limitations and modem problems

Rarely, the problem is hardware, such as a modem malfunction or a conflict with baseband firmware.

• 🔨 Unofficial Unlocking of Bootloader.
• 🔄 Custom Recovery Firmware (TWRP).
• 📡 Falls or impacts (damage to the antenna module).

Signs of hardware problem:

• The blacklist does not work for a specific SIM-map.
• All calls are missed, not just from the blacklist.
• B Settings → SIM-maps and mobile networks → Status. SIM-The card displays an error (e.g., “No service»).

Decisions:

1. Check the IMEI (must match the box):

*#06#

1. If the IMEI is reset (shown as 000000000), restore it via the Mi Flash Tool or contact the service.
2. Please use the baseband modem via Fastboot:

fastboot flash modem NON-HLOS.bin


fastboot flash fsg fsg.mbn

⚠️ Warning: Modem firmware is a risky operation, if you're not sure, you should contact the service center. Wrong files can permanently disable the modem.

7. Alternative ways to lock numbers on Xiaomi

If the standard blacklist doesn’t work hard, use alternative methods:

• 📲 Blocker apps: Call Blocker (from F-Secure) Blacklist Plus Should I Answer)
• 📞 Operator Blocking: Activate the service with the mobile provider (see table above).
• 🔕 Do Not Disturb: Set up exceptions for all contacts except those blocked:

Settings → Sounds and vibrations → Do not disturb → Allow exceptions → Contacts only

Lifehack for MIUI: If the number is calling via WhatsApp or Viber, block it directly in the messenger.

• Open the chat room. → ⚙️ → Block it.
• In Telegram, you can add a number to Settings → Privacy → Blacklist.

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If none of these methods worked, try resetting the network to factory settings (Settings → System → Reset → Network Reset) this will remove all stored Wi-Fi and Bluetooth devices, but often resolves locking issues.

FAQ: Frequent questions about the blacklist on Xiaomi