The App Lock feature on your Galaxy S25 Ultra keeps your private apps secure by requiring authentication before access. It’s a reliable way to protect sensitive apps like Messages, Gallery, or Banking apps. However, if App Lock suddenly stops working, apps may open without asking for a password, PIN, or biometric verification.
This problem often appears after software updates or incorrect privacy settings. Thankfully, there are several ways to restore App Lock’s proper function.
Why App Lock Might Not Be Working on Your Galaxy S25 Ultra
- Secure Folder or App Lock feature is disabled.
- Biometrics or PIN authentication is not set up.
- Background usage restrictions interfere with App Lock.
- Cache or data issues with the security service.
- Outdated One UI or system software.
Make Sure App Lock is Enabled.
Sometimes, App Lock might have been turned off after a software update or phone restart. Re-enabling it ensures your apps are locked again.
- Open Settings, and then tap Security and privacy.
- Tap App lock, and then toggle it on.
If prompted, set a lock method such as a PIN, pattern, or fingerprint to activate the feature.
Check App Lock Permissions.
App Lock requires special permissions to function correctly. Without these, it won’t be able to block access to your selected apps.
- Open Settings, and then tap Security and privacy.
- Tap App lock, and then ensure all required permissions are granted.
If permissions were denied earlier, re-enable them and test again by opening a locked app.
Verify That Lock Type Is Set Up Properly.
App Lock depends on your screen lock security. If your fingerprint or PIN setup was removed or changed, the feature may malfunction.
- Open Settings, and then tap Lock screen.
- Tap Screen lock type, and then make sure a secure method like PIN or fingerprint is enabled.
After this, go back to App Lock and test if it prompts for authentication.
Remove Battery Optimization for App Lock.
Battery optimization can sometimes restrict App Lock from running in the background, causing it to fail when launching protected apps.
- Open Settings, and then tap Battery and device care.
- Tap Battery, then tap Background usage limits.
Add App Lock or Security Services to the list of apps that are not put to sleep. This keeps it active and responsive at all times.
Clear App Lock or Security Service Cache.
Corrupted cache files can cause App Lock to stop enforcing protection. Clearing them can restore normal functionality.
- Open Settings, and then tap Apps.
- Tap the three-dot icon, choose Show system apps, then find and tap Security Services or App Lock.
Tap Storage, then tap Clear cache and Clear data. Re-enable App Lock afterward.
Update Software.
Outdated firmware or One UI versions can introduce bugs that affect App Lock. Updating your device ensures all security features run smoothly.
- Open Settings, and then tap Software update.
- Tap Download and install, and follow the on-screen instructions if an update is available.
After updating, restart your phone to apply the changes.
App Lock is an essential feature for protecting your personal apps. Once you’ve tried these steps, it should begin prompting for authentication again, keeping your Galaxy S25 Ultra secure and private.
FAQs
Why does App Lock keep turning off by itself?
It can happen when battery optimization puts the feature to sleep or after major system updates. Disable optimization to prevent this.
Can App Lock work with fingerprint unlock?
Yes. You can use fingerprint authentication for faster access instead of entering your PIN or pattern each time.
Will clearing App Lock data delete my locked apps?
No. It only resets the App Lock configuration. You’ll need to reselect which apps to protect afterward.
