1. Go to 
Settings > 
Apps > App lock.
2. Tap
at the upper-right corner of the phone.
3. Manage App lock password settings.
• Tap Change password type to change the App lock password type and the password itself.
• Tap
to enable Unlock with fingerprint. You can add a fingerprint unlock for App lock.
• Tap
to enable Face unlock. You can add a face unlock for App lock.
• Tap
to enable Add Mi Account . It is recommended to add your Mi Account before you use App lock. If you forget the App lock password, you can reset it with the Mi Account. Otherwise, you can only perform a factory reset.
Settings > Apps > App lock.2. Tap
at the upper-right corner of the phone.3. Manage App lock password settings.
• Tap Change password type to change the App lock password type and the password itself.
• Tap
to enable Unlock with fingerprint. You can add a fingerprint unlock for App lock.• Tap
to enable Face unlock. You can add a face unlock for App lock.• Tap
to enable Add Mi Account . It is recommended to add your Mi Account before you use App lock. If you forget the App lock password, you can reset it with the Mi Account. Otherwise, you can only perform a factory reset.