The lack of incoming SMS on a Redmi phone with MIUI firmware is most often caused by the aggressive operation of the built-in antivirus and battery optimizer, which mistakenly block messages from banks and verification services even before they are displayed in the notification.
In this guide we will analyze in detail all possible causes of the failure, ranging from banal overcrowding of the SIM card memory to complex conflicts system applications. You don't need to be a telecommunications expert to troubleshoot a problem—just follow the suggested steps one by one. We will pay special attention to notification settings and access rights, since it is in these sections that the truth most often lies when diagnosing problems on smartphones Redmi.
Checking the physical state of the SIM card and network
Before delving into the deep settings of the operating system, it is necessary to eliminate physical factors that affect the quality of communication. Often the problem lies on the surface: poor contact between the SIM card chip and the phone reader or temporary malfunctions in the operation of mobile operator towers. Try removing the tray SIM cards and carefully inspect the contacts for oxidation or contamination. Gently wipe the chip with a soft cloth, without using aggressive chemical solutions, and install it back until you hear a characteristic click.
If you have a dual-SIM device, it makes sense to move the card to another slot. Sometimes one of the slots may not work correctly due to a manufacturing defect or mechanical damage. It’s also worth checking whether your operator’s SMS reception service is active by calling support or checking your personal account. In rare cases, the operator blocks the reception of messages in the presence of debt or suspicious activity.
⚠️ Attention: If you are using an old SIM card cut from Mini or Micro format for Nano, its thickness may be larger than standard. This leads to poor contact and periodic network losses, which directly affects message delivery.
To quickly diagnose the network condition, you can use the engineering menu or simply watch the signal indicator. Make sure your phone is not in Airplane mode and that the correct network type is selected. In the mobile network settings, try forcefully switching the mode from 4G/LTE to 3G or 2G for a few minutes, and then switching back. This manipulation forces the modem to re-register with the operator’s network, which often solves the problem of frozen sessions.
Try inserting your SIM card into another phone. If SMS do not arrive there either, the problem is definitely on the side of the operator or the card itself, and not the Redmi smartphone.
Setting up a messaging application
The shell MIUI by default uses its own “Messages” application, which has advanced functionality for blocking spam. Sometimes filtering settings work falsely, sending important verification codes to a hidden folder or completely blocking their receipt. Go to the messages application, tap on the three dots in the corner of the screen and select "Settings". Here you need to check the "Blocked" section to make sure that the sender's number is not blacklisted by mistake.
Particular attention should be paid to access rights and the operation of the application in the background. System Android on smartphones Redmi tends to “kill” processes that are not actively used to save battery power. If the message application was closed by the system before the notification arrived, you may simply not see it. Open your phone's settings, go to the "Applications" section and find "Messages" in the list.
- 📱 Select "Activity Control" and set the value to "No restrictions" so that the system does not close the application.
- 🔔 Go to the "Notifications" section and make sure that the "Allow notifications" switch is active, and sounds and pop-ups are turned on windows.
- 🗑️ Go to the "Memory" item and click "Clear cache", but do not delete the data so as not to lose the correspondence history.
It is also worth checking if the "Smart messages" function or sorting by category is enabled, which can hide transactional messages from banks in separate tabs. Disabling unnecessary functions to simplify the interface sometimes returns the standard behavior of the app. If you are using a third-party SMS client, for example Google Messages, make sure that it is set as the default application in the appropriate section of the system settings.
Resetting network settings and connecting APN
One of the most effective methods for solving communication problems is a complete reset of network settings. This procedure does not delete your personal files, photos, or contacts, but it does reset your mobile, Wi-Fi, and Bluetooth settings to factory defaults. This is especially useful if you recently changed operators or moved to another region, where incorrect connection profiles may have remained.
To perform a reset, go to menu Settings → Connection and sharing → Reset Wi-Fi, mobile networks and Bluetooth. Confirm the action by clicking the appropriate button at the bottom of the screen. After rebooting the phone, you will need to re-enter the passwords for your Wi-Fi networks and re-pair your Bluetooth devices, however, the access point parameters APN should be updated automatically by the operator.
| Parameter | Default value | Failure action |
|---|---|---|
| Point type access | default,supl,mms | Check for commas |
| APN protocol | IPv4/IPv6 | Change to IPv4 |
| Access point name | Internet (or operator name) | Create a new point |
| MCC/MNC | Automatically | Do not change manually |
In some cases, automatic configuration of an access point does not work correctly, especially on custom firmware or after global updates. Then you need to create a new access point manually. Go to the mobile network settings, select your SIM card and open the "Access Points (APN)" item. Click the add new point button and enter the data received from the official website of your mobile operator. After saving, be sure to activate this point by clicking on the circle next to it.
☑️ Actions when resetting the network
The impact of system updates and energy saving
Firmware updates MIUI often bring not only new functions, but also unexpected bugs that affect the stability of communication modules. If a problem with SMS appeared immediately after updating the system, there is a high probability of a software conflict. In this case, it is worth checking for more recent security patches that may have been released to correct this error, or, conversely, consider rolling back to a previous version if the device allows this.
Aggressive energy saving system is the scourge of modern smartphones Xiaomi. It can limit the background activity of system services responsible for receiving signals from base stations. Go to the "Battery and Performance" section and check the power saving settings. Try switching the operating mode from “Balanced” to “Productive” for a while to test the hypothesis. This section also contains a list of applications that are prohibited from running in the background - make sure that system services are not blocked there.
⚠️ Attention: The energy saving settings interface may differ depending on the version of MIUI (12, 13, 14 or HyperOS). If you do not find the described items, use the search in the settings by entering the query “autostart” or “battery.”
Sometimes the culprit is the “MIUI Optimization” function, which is hidden in the menu for developers. It is designed to speed up the system, but often breaks standard notification mechanisms. To disable it, you need to activate developer mode by clicking on the build number 7 times in the “About phone” section, then go to additional settings and find the “Enable MIUI optimization” item. After disabling this function, the phone must be rebooted.
How to get to the developer menu safely?
Go to Settings → About phone. Quickly click on the line “MIUI Version” or “OS Version” about 7 times in a row until the message “You have become a developer” appears. After this, a new menu “For Developers” will appear in the “Advanced” section.
Conflicts with third-party applications and antiviruses
User-installed applications can intercept rights to read and send SMS, while blocking legitimate traffic. This is especially often done by various memory cleaners, antiviruses, and caller ID applications. If you have recently installed such software, try temporarily uninstalling it or revoking its permissions to work with messages in the privacy settings.
Check the list of applications that have access to SMS. Go to Settings → Privacy protection → Permission manager → Messages. This list should not contain suspicious apps that you do not trust. If you see an app that inherently shouldn't work with text messages (like a flashlight or calculator), immediately deny it access.
- 🛡️ Third-party antiviruses often duplicate the functions of the built-in defender Security, creating filter conflicts.
- 📬 Applications for organizing tasks may request access to SMS to automatically create reminders, which sometimes leads to failures.
- 🚫 Malicious software can block SMS from banks in order to hide the fact of money theft, so checking for viruses is mandatory.
For a deep scan of the system, you can use the built-in security scanner from Xiaomi, which runs on the engine Avast or AVL (depending on the firmware region). Run a full scan of your device and remove all threats found. It is also worth checking whether messages are forwarded to another number, which could be done by a malicious script.
Third-party launchers and themes rarely affect SMS, but custom Magisk modules or modified system files can completely disrupt the operation of the radio module.
Radical measures: reset to factory settings
If none of the above methods helped restore the functionality of the messaging service, the last software method remains - a complete reset of the device to factory settings. This measure is guaranteed to eliminate any software errors accumulated during use, but requires the preliminary saving of all important data, since information from the internal memory will be deleted.
Before starting the procedure, be sure to create a backup copy of contacts, photos and documents in cloud storage Mi Cloud or on your computer. Make sure the battery is at least 50% charged to prevent your phone from turning off while erasing data. Go to menu Settings → About phone → Reset settings → Delete all data.
After the phone reboots and goes through the initial setup, do not restore all applications from the backup at once. First, check the operation of SMS on a “clean” system. If messages arrive properly, then the problem was in one of the previously installed applications or in system garbage. Start installing apps one at a time, checking the connection functionality after each installation to identify the culprit.
⚠️ Attention: After resetting the settings, the anti-theft function (FRP) may ask for the password from the Google account that was previously synchronized with the phone. Make sure you remember your login details, otherwise access to your device will be blocked.
Before performing a hard reset, try simply deleting the Messages and Phone app updates through the app settings menu. Sometimes this helps without losing personal data.
Why do SMS arrive with a delay of several hours?
The delay is often due to overload of operator channels on holidays or because the phone was unable to register on the network for a long time after leaving the coverage area. Also, the reason may be the deep sleep mode, from which the device cannot quickly wake up to receive a signal.
Could there be a problem that the phone is a dual-SIM phone?
Yes, in the settings of dual-SIM modes, sometimes an option is selected where one card is used only for the Internet, and the other for calls, and the SMS settings may go wrong. Check which card is selected for sending and receiving messages by default.
What to do if you do not receive SMS from only one number?
Most likely, this number was accidentally blacklisted or included in the spam blocking list. Check your blocking settings in the Messages app and your history of blocked events. It is also possible that the sender is using a gateway that is blocked by your operator.
Does changing the region in the phone settings affect SMS reception?
Changing the region can change frequency settings and lists of roaming partners, which could theoretically affect registration on the network. It is recommended to set the region that corresponds to your actual location or the region where the device was purchased.
How to check if your SIM card is blocked by your operator?
Try calling from this number to another phone. If the call does not go through or you hear a message that the subscriber is unavailable, call the operator from another phone to clarify the status of your SIM card and balance.