Modern smartphones like the Redmi 9T take dozens of calls every day, many of which carry no payload, but only distract or try to deceive the owner. The built-in MIUI system offers powerful tools to protect against unwanted content, but they are not always activated by default or require fine-tuning to the user’s needs.
Effectively blocking spam not only helps to keep your peace of mind, but also protects your personal data from fraudulent schemes that are becoming more sophisticated. Owners of Xiaomi devices have access to a database that is updated in real time, which significantly increases the chances of preventing contact with malicious numbers.
In this article, we will take a closer look at the process of activating all the security levels available on your gadget, and you will learn not only to turn on standard filters, but also to create your own rules that will work more effectively than any third-party application.
Basic security settings in the Phone application
The first step to clean up the call list is to properly configure the standard Phone app, which is preinstalled on the Redmi 9T. This is where the main switch is responsible for interacting with the global database of unwanted numbers.
First, you open the app and go to the settings menu, which is usually hidden behind three dots or a gear in the corner of the screen. Find the Antispam or Block section, which is where the main levers of incoming traffic are concentrated.
Activate the spam filter slider, and then the system prompts you to download the current databases. This action is critical, since without fresh data, the phone will miss known fraudulent numbers.
- 📞 Open the Phone app and click on the gear icon in the corner.
- 🛡️ Select Antispam in the list of options.
- 🌍 Turn on the spam filter toggler and allow database updates.
- 📲 Make sure that the option to block hidden numbers is active at your request.
⚠️ Note: When you first turn on filtering, the system may ask permission to access contacts and call history. Without this functionality, smart sorting will not work, so access must be provided.
Use of the Security Application for Deep Filtering
In the MIUI ecosystem, the central permissions and security management node is the Security system application, which has deeper rights than a standard dialer, and allows you to configure complex lock scenarios.
Go to the app and select the Antispam section, and here you will see statistics of blocked calls and messages, and you can also go to advanced settings, and this is where the smart lock is set up, which analyzes the behavior of the caller.
Particular attention should be paid to filtering settings SMS-The system can automatically hide messages that contain links to suspicious sites or keywords characteristic of casino and microloan advertising.
You can create your own blacklist manually by adding specific numbers that continue to be dialed, and you can also add prefixes to block entire series of numbers, such as those starting with certain numbers.
- 📂 Launch the Safety app (green icon with lightning).
- 🚫 Go to the Antispam section and click on the settings gear.
- 📝 Select Lock Settings for Calls and Messages Separately.
- 🔒 Activate Only from Contacts for maximum silence if necessary.
⚠️ Warning: Enabling Contact Only mode will prevent you from receiving calls from couriers, taxis or doctors that are not in your notebook.
☑️ Checking the filtering settings
Set up a blacklist and exceptions
The flexibility of Xiaomi’s system is that it can fine-tune the rules: You can create a blacklist that ignores certain numbers, or vice versa, a whitelist for priority contacts.
To add a number to the blacklist manually, go to the call log, click on the desired number and select the Lock option. This number can no longer reach you, and the caller will hear the beeps as if the phone is turned off.
For more complex tasks, use the smart rules feature, for example, you can set up a lock on all numbers that are not saved in contacts but come with codes from other countries, which is especially important for protecting against international fraud.
Remember the exceptions. Even with hard filtering settings, emergency numbers or important organizations should take priority.
| Type of rule | Description of action | Recommendation |
|---|---|---|
| Keyword blocking | Hiding SMS with certain text | Add the words "credit", "winning", "share" |
| Blocking of unknowns | Rejects all numbers outside of contact | Only enable when there is strong spam |
| Quiet regime | No calls, but they're fixed. | Perfect for night time. |
| Whitelist | Only selected numbers are missed. | Add relatives and work |
What does the caller see when they lock?
Blocking advertising SMS and messages from services
Emails from banks, stores and delivery services are often more annoying than live spam calls. Redmi 9T has a mechanism to sort these messages into a separate folder without disturbing the user with notifications.
In the message filtering settings, enable the Ad Filter option. The system will analyze the content of incoming SMS and, if it detects signs of mass mailing, hide the message in the Spam folder within the Message application.
For advanced users, you can customize keywords, you can type in the names of banks or brands that you don't care about, and this will help you clear inbox from intrusive sentences.
It is important to check the spam folder periodically, as important confirmation or notification codes from government agencies may accidentally get there. Automatic filtering does not always work perfectly, so human control is necessary.
- 💬 Open the Messages app and click on the menu icon.
- ⚙️ Go to Settings. → Antispam.
- 🔑 Add keywords (such as “Bets”, “Lending”) to the blacklist.
- 🗑️ Clean your spam folder regularly to make room.
💡
Use response templates to auto-respond to spam, and you can set the settings to automatically send a message "Don't call me again" when you receive a call from a locked number.
Third-party applications and their compatibility with MIUI
While the Redmi 9T’s built-in tools are powerful, some users prefer third-party solutions such as Getcontact, NumBuster or Kaspersky.
MIUI aggressively manages background processes to save battery. If you install a third-party number detector, be sure to go to the battery settings and allow the app to auto-start and run in the background.
Without these settings, the detector won't be able to intercept the incoming call in time, and the phone will ring before the app has time to show the name of the caller, a common problem that beginners face.
Privacy is also a good thing to remember: when you install third-party determinants, you often agree to transfer your phone book to the developer servers.
⚠️ Warning: Do not set multiple number detectors at the same time. They will conflict with each other, which will lead to battery discharge and unstable operation of the call.
💡
Xiaomi’s built-in anti-spam works faster and safer than third-party counterparts, as it has deep rights in the system and does not consume additional battery power.
Solving Filtration Problems
Sometimes users are faced with a situation where anti-spam stops working or blocks the desired calls, most often the problem lies in outdated databases or failures in the security application.
Try clearing the Security app cache through your phone's settings, and then look in the Security app list, click Memory, and select Clear. This won't delete your settings, but it will update the modules.
If the problem is not resolved, check the date and time on the device. Incorrect time can disrupt synchronization with the servers of the Spam database updates, which will cause filtering to cease to be relevant.
In a pinch, you can reset the Phone app to factory settings, which will return all lock settings to the original state, after which you will need to re-activate the filters.