How to permanently block SMS from unwanted subscribers on Xiaomi Redmi 7A

Spam and scammers are a headache for Xiaomi Redmi 7A owners, especially if the number is in the databases of mass mailings. Unlike modern flagships, the budget model does not have built-in anti-spam with artificial intelligence, but blocking unwanted SMS on it is still possible. The problem is that standard methods (for example, through the message menu) often work unstable due to the features of the MIUI firmware for the Redmi 7A.

In this article, we have 5 proven methods, including hidden operating system settings, third-party applications and interaction with a mobile operator. We will discuss why blocking through a standard menu may not work on your version of MIUI, and what to do if a spammer uses spoofing. All instructions are adapted to the Redmi 7A with its hardware limitations (1 GB of RAM, Snapdragon 439).

Why the standard SMS lock on Redmi 7A doesn't work

Redmi 7A owners often find that after adding a number to the blacklist, messages from the number continue to flow, and the reason lies in three key features:

• 📱 The stripped-down version MIUI: On the Redmi. 7A lightweight MIUI Go Edition, which does not have a deep integration module with Xiaomi services (for example, Security App works in limited ways).
• 🔄 Message caching: Messages application can display already blocked SMS due to synchronization error with the telephony.db database.
• 🕵️ Spoofing numbers: Scammers use the sender number swapping technology, and the system perceives each new message as unique.

In addition, Redmi 7A does not have automatic spam filtering (unlike Redmi Note 10 and later), so the user has to block each number manually, if you notice that after blocking, SMS continue to come with the same text, but from different numbers - this is a sure sign of spoofing.

⚠️ Attention: On Redmi 7A firmware MIUI 12.5 and below, lock through the standard Messages menu → Three points. → The blacklist only works for numbers stored in contacts. Alternative methods are required for unsaved senders.

Method 1: Blocking through the standard Messages app

Despite the limitations, basic locking in MIUI can help in 60% of cases.

1. Open the Messages app and find a spam message.
2. Click on the message and hold it for 2 seconds until the context menu appears.
3. Select Details → Three points (⋮) → Add to the blacklist.
4. Confirm the action in the pop-up window.

If the item Add to the blacklist is not:

• 🔧 Go to Settings. → Annexes → Application management → Communications → Permits and enable access to contacts and SMS.
• 📲 Update the Messages app via Google Play Market (if available for your region).

Check the version of the Messages app (must be at least 6.7.14)

Enable permissions to access SMS and contacts

Make sure the spammer number is not hidden (does not appear as “Unknown”)

Restart your phone after you add it to the blacklist-->

On Redmi 7A with firmware older than 2021, the blacklist is stored in the file /data/data/com.android.providers.telephony/databases/mmssms.db. If the lock is reset after the reboot, this is a sign of database damage.

Method 2: Using the built-in Security App

Xiaomi's Security app has a hidden SMS blocker that is more stable than the standard messaging menu.

1. Open Security (Shield icon)
2. Go to the Blocking section (or the Blacklist in older versions).
3. Select the SMS tab.
4. Click Add and enter the spammer number manually or select from the story.

Features of the method:

• 🔒 It works even for numbers not stored in contacts.
• 📊 Logs blocked messages (available on the way Security) → Lockdown → Journal).
• ⚡ Requires AutoRun background enabled for Security (Settings) → Annexes → Application management → Security → Auto-start).

⚠️ Note: If after the update MIUI Security is gone – it can be restored through Settings → Annexes → Show all applications → Unplugged and back on.

Method 3: Third-party applications for blocking SMS

For Redmi 7A, only lightweight anti-spam apps are suitable, since the device has only 1 GB of RAM.

• 📞 Truecaller (weight) ~30MB: Blocks spam from a database with 500 million numbers, minus requires registration by phone number.
• 🛡️ SMS Blocker (weight) ~5MB: Local locking without cloud checks, suitable for weak devices.
• 🔍 Should I Answer? (weight) ~10 MB: Specializes in fraudulent numbers, integrates with MIUI.

How to set up Truecaller on Redmi 7A:

1. Download the app from Google Play.
2. When you first start, allow access to SMS, contacts and phone calls.
3. Enable the option to block spam in the application settings.
4. Add problem numbers manually through the Blacklist → Add a number.

💡

Before installing anti-spam, clear the Messages cache (Settings → Applications → Messages → Clear cache) to prevent conflicts when syncing databases.

Warning: Some anti-spam apps (such as Hiya) may slow down Redmi 7A due to background activity. Once installed, check RAM consumption in Settings → About Phone → System Status → Memory Use.

Method 4: SMS blocking via mobile operator

If spam is coming from a single operator (e.g. MTS or Beeline), it is more effective to block them at the network level.

• 📶 MTS: Send a text message with the text of the BLOC [number] to the short number 111. Example: BLOC 89123456789.
• 📶 Beeline: Dial it up *110*789# (where 789 — last digits of the spammer number and call.
• 📶 MegaFon: Go to your personal account, section Services → Protection against spam.
• 📶 Tele2: SMS STOP [number] to 777.

Advantages of the method:

• ✅ It works even if the phone is turned off.
• ✅ Blocks spoofing (number swapping) at the network level.
• ✅ Does not load the Redmi processor 7A.

⚠️ Note: Operators only block numbers on their network if the spammer uses virtual numbers (e.g. via a network) SIP-This method won't help, so combine it with third-party applications.

Method 5: Manual editing of the SMS database (for advanced)

If all of the above methods fail, you can manually edit the system database mmsms.db, where all SMS are stored. This method requires root rights and is suitable only for advanced users.

Step-by-step:

1. Install Root Explorer or FX File Explorer with root support.
2. Go to /data/data/com.android.providers.telephony/databases/.
3. Copy the file of mmssms.db on SD-map (backup copy!).
4. Open the file in SQLite Editor and find the blacklist table.
5. Add the spammer number in +79123456789 (with country code).
6. Save the changes and restart the phone.

Alternative method without root:

• 🔧 Use it. ADB-Adding a number to the blacklist: adb shell content insert --uri content://sms/blacklist --bind number:s:"+79123456789"
• 📱 To do this, connect Redmi. 7A PC, turn on Debugging on USB (Settings → The phone. → Version. MIUI — Press 7 times, then Settings → Additionally. → For developers → Debugging by USB).

Additional measures: how to reduce the amount of spam

In addition to blocking, you can reduce the likelihood of your number getting into spam databases:

• 🔐 Do not publish the number in the open access (social networks, forums, ads).
• 📝 Use the second number to register on websites (for example, through Google Voice or virtual ones). SIM).
• 🛡️ Enable spam protection in your Google account (Google Settings) → Account management → Security → Spam settings).
• 📵 Turn it off. SMS-Advertising from the operator (usually through the USSD-*111# or in your personal account).

If spam is coming from short numbers (e.g. 1234, 5678), it is most likely service mailings from banks or government services.

💡

The combination of methods gives the best result: use the lock through “Security” + anti-spam application + operator service.

FAQ: Frequent questions about blocking SMS on Redmi 7A