If App Lock is not working on your Xiaomi 15 Ultra, protected apps may open without asking for a password or biometric verification. This defeats the purpose of the feature and can put your private data at risk. The issue usually comes from permission limits, battery restrictions, or misconfigured App Lock settings, all of which can be fixed with a few careful checks.
Why App Lock Is Not Working on Your Xiaomi 15 Ultra
- App Lock is turned off for specific apps.
- Required permissions for App Lock are disabled.
- Battery optimization is restricting the Security app.
- Face unlock or fingerprint verification is failing.
- The Security app cache is corrupted.
1. Make Sure App Lock Is Enabled for the App
App Lock works on a per app basis. If the app is not selected, it will open normally even if App Lock is turned on globally.
Open Settings, and then tap Privacy and security.
Tap App Lock, and then turn on the toggle for the affected app.
2. Recheck App Lock Authentication Method
If biometric authentication fails, App Lock may skip verification altogether. Switching or reconfirming the unlock method often restores proper behavior.
Open Settings, and then tap Privacy and security.
Tap App Lock, and then reselect Fingerprint, Face unlock, or Password.
3. Allow App Lock to Run Without Restrictions
Battery optimizations can stop App Lock from triggering in the background. This is common when the system aggressively manages power usage.
Open Settings, and then tap Battery.
Tap App battery saver, and then set the Security app to No restrictions.
4. Enable Required Permissions for the Security App
App Lock depends on system level permissions to monitor app launches. If these permissions are disabled, App Lock will not activate.
Open Settings, and then tap Apps.
Tap Manage apps, and then select Security to enable all required permissions.
5. Clear the Security App Cache
A corrupted cache can cause App Lock to behave inconsistently. Clearing it refreshes the service without deleting your personal data.
Open Settings, and then tap Apps.
Tap Manage apps, select Security, and then clear the cache.
6. Restart the Phone to Refresh Services
Some App Lock issues persist until system services reload. A restart helps reset background processes tied to app protection.
Swipe down from the top to open the control panel, and then tap the Power icon.
Tap Restart, and then wait for the phone to boot up fully.
Once App Lock is properly configured and allowed to run freely, it should protect your apps every time you open them. After these fixes, locked apps should immediately ask for authentication again.
FAQs
Why does App Lock work for some apps but not others?
App Lock must be enabled individually for each app. If one app is unchecked, it will bypass protection completely.
Does battery saver affect App Lock on the Xiaomi 15 Ultra?
Yes. Aggressive battery saving can prevent the Security app from running in the background, which stops App Lock from activating.
Is it safe to clear the Security app cache?
Yes. Clearing the cache does not remove settings or data, and it often fixes App Lock issues caused by temporary files.
