A situation where a Xiaomi smartphone suddenly stops receiving or making calls can take you by surprise at the most inopportune moment.The device's screen can show lock messages SIM-card, require input PUK-It's a code or a simple "No Network" display, and it's for a variety of reasons: from the simple input of the wrong type. PIN-several times before more complex problems with IMEI-address or blockage by the mobile operator.
Understanding the nature of the problem is the first and most important step to restore communication. Owners of Xiaomi, Redmi and POCO devices often encounter features of the MIUI or HyperOS shell that can interpret network failures as a lock, it is important not to panic and consistently check all possible causes, from simple settings in the phone menu to contacting the salon.
In this article, we will discuss in detail all scenarios in which a number may become unavailable, and provide step-by-step instructions for restoring access. PUK-How to avoid complete locking of the device by international identifier.
Reasons for blocking numbers on Xiaomi devices
Before you go into action, you need to clearly define why your number was blocked, most often the problem lies in the actions of the user or automatic security systems. PIN-Security system. SIM-Cards automatically block access to the network to protect your data from unauthorized use.
Another common reason is debt to the operator: if the balance is negative for too long, the operator suspends the provision of services, which on the screen of the smartphone looks like a complete lock of the number, and you should also consider the possibility of locking by IMEI if the device is listed in the databases of lost or stolen, although this is less common and usually applies to used equipment.
⚠️ Note: If your phone was bought with your hands and suddenly stopped catching the network after upgrading or changing SIM-maps, there is a high probability that IMEI The device has been changed software or the phone itself is wanted.
Sometimes users activate the Blacklist or Antispam feature in MIUI settings by accidentally adding important contacts or even their own number to the feature testing, in which case the phone formally works but blocks incoming calls from certain subscribers, and don’t discount the technical malfunctions in the smartphone’s communication module, which can simulate a lock on the part of the operator.
Unlocking SIM-map PUK-code
When the phone asks PUK-Personal Unblocking Key, which means that the limit of attempts to enter PIN-No random combinations should be entered in this field, after ten wrong attempts. SIM-The card will be destroyed programmatically and the number can be restored only by re-releasing plastic from the operator. PUK-Code is your only key to saving data on a SIM.
There are a number of ways to find this code, and the easiest way to do that is to look at the plastic card holder that came with the same card. SIM-The code is usually hidden under a protective layer and consists of 8 digits. If the card is lost, the code can be found in the personal account of the mobile operator on the official website or in the mobile application by logging in via Wi-Fi.
The process of unlocking on Xiaomi is as follows:
- 📱 Enter the 8-digit PUK-code in the field that appears on the lock screen.
- 🔢 The system will suggest inventing a new PIN-code (usually 4 digits).
- ✅ Confirm the new code by re-entering.
If you don't remember PUK If you don't have access to your personal account, the only safe option is to call the operator's support service from another phone, the operator will identify the identity from the passport data and dictate the code. PIN-code when turning on the phone in the security settings to avoid a repeat of the situation.
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Save it. PUK-code in a secure location, such as biometrically protected notes or write it down in a paper notebook that is stored separately from the phone.
Removal of the lock by the operator
Operator blocking is an administrative restriction that is only removed through the provider’s communication channels, most often due to financial reasons or suspicious activity on a number that automatic systems consider spam or fraud, in which case standard smartphone reboots will not help.
To solve the problem, you need to contact technical support, this can be done through an in-app chat, through a personal account on the site or by calling the hotline. Be prepared to confirm that the number belongs to you. In some cases, if the blocking is associated with suspected spam, the operator may ask you to write a statement.
The recovery process usually takes from a few minutes to 24 hours.
- 📞 Call the operator from another number on the same network.
- 🆔 Pass the identification procedure (name name, passport data).
- 💳 Pay the debt if the financial blockage.
- ⏳ Expect to remove restrictions, sometimes you need to restart the device.
⚠️ Note: If your number was blocked for spam, but you didn't, request details of calls. SIM-The card was cloned or used in the lost device by third parties.
It is worth noting that in rare cases, operators block numbers that have not been used for a long time (Sleep Mode).Reactivation may require a personal visit to the communication salon with a passport. SMS-Notifications from the operator of nearing end of balance or suspicious activity, as they often precede a complete lock.
Software unlocking through MIUI settings
Sometimes the problem isn't with the SIM card, but with the software settings of the Xiaomi smartphone itself. MIUI's shell has advanced security features that can block calls. Check the Antispam and Blacklist sections. You may have accidentally activated Do Not Disturb mode or added a contact to the blacklist.
To check your settings, go to the Security app (green shield icon) and look for the Blacklist or Lock section, where you can see all the locked numbers and lock rules. If you see your number or caller number on the list, just delete that entry or turn off the corresponding switch.
☑️ Checking the lock settings
You should also check your network settings. Go to Settings. → SIM-maps and mobile networks. Make sure that the right SIM-The card includes the default option for calls and the Internet, sometimes helping to reset the network settings to factory, which does not delete personal data, but returns network settings to the original state.
In some cases, re-registration on the network helps. 10-15 Then turn it off. If that doesn't work, try to remove it. SIM-Make sure the card is set correctly and fits tightly to the tray contacts.
IMEI problems and their solution
The most serious problem that a Xiaomi owner can face is the loss or blocking of IMEI. IMEI (International Mobile Equipment Identity) is a unique hardware identifier. If the status bar instead of the operator name says “Emergency Calls Only”, and the IMEI phone settings show as “Null” or “Unknown”, then the software failure erased this identifier.
Without the right IMEI, the phone won't be able to log in to the operator's network, which often happens after unsuccessful flashing attempts, resetting settings through an engineering menu, or using unofficial software, and IMEI recovery is a complex procedure that requires specialized knowledge and tools.
For diagnosis, enter the command in the "Phone" application:
*#06#If nothing happens after you type in a command or zeros are displayed, the problem is confirmed. MediaTek processor owners sometimes benefit from using a Maui Meta or SN Writer utility, but Snapdragon processors require more sophisticated tools like QPST and root rights.
| Symptoms. | Possible cause | Difficulty of solution |
|---|---|---|
| IMEI = Null / Unknown | Firmware rendezvous NV-memory | High (PC needed) |
| Blocking on the GSMA base | Phone wanted. | Impossible (officially) |
| No network after firmware | The wrong firmware region | Medium (flashing) |
| Request to unlock Mi Account | Blocking activation | Medium (requires an account) |
Can I change the IMEI legally?
Prevention of blockages and important tips
To avoid future lock problems, a few simple digital hygiene rules should be followed: Regularly update your MIUI/HyperOS operating system to the current version, as updates often contain corrections for communication module errors; Do not use questionable applications to “accelerate the phone” or “change the IMEI” found in unverified sources.
Always keep a box from your phone and documents on your phone. SIM-A box with a factory card. IMEI You may need to prove ownership of the device if you lock it on a database of stolen phones, and keep your balance on the phone and avoid prolonged periods of downtime without activity.
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Regularly backing up your contacts to the Google or Mi Cloud cloud will protect your phone book even in the event of total loss. SIM-card-breaking.
If you buy a phone with your hands, be sure to check its IMEI through special services on the Internet before buying, this will save you from buying a “brick”, which will be blocked when you first register on the network. Be careful when entering unlock codes and do not be afraid to contact specialists if you are not sure of your actions.