1. To lock your device screen, press the Power/Lock button.
   
2. To unlock your device screen, press the Power/Lock button.
   
3. To change security lock type, swipe down from Notification bar.
   
4. Tap the Settings icon.
   
5. In the DEVICE tab, tap Lock screen.
   
6. Tap Screen lock.
   
7. Tap Desired screen lock type.
   Note: For this demonstration “Fingerprint” was selected.
   
8. Swipe your fingertip downwards over the Home button. You will need to swipe the same finger 10 times to register your fingerprint. 
   
9. Tap REGISTER to register this fingerprint again by swiping in the most comfortable direction. Tap DONE to skip this step.
   Note: For this demonstration “DONE” was selected.
   
10. Enter a backup password of at least 6 characters, including at least 1 letter and 1 number and tap CONTINUE.
    
11. Reenter the backup password and tap OK.
    
12. Select display options for notifications on the lock screen, then tap DONE.
    
13. Your device now has a fingerprint screen lock type.
    
14. To adjust the lock screen timeout setting, from the Lock screen screen, tap Secured lock time.
    
15. Select the desired lock time. 
    
16. To unlock your device screen place your finger on the Home button.
    
17. To register additional fingerprints, from the DEVICE tab in settings, tap Finger Scanner.
    
18. Tap Fingerprint manager.
    
19. Confirm your identity by swiping your fingerprint. 
    
20. To deregister a fingerprint, tap Add icon and follow the process detailed in Steps 8 and 9.
    
21. To deregister a fingerprint, tap the More icon, then tap Select.
    
22. Select the Desired fingerprint and tap the Delete icon.
    
23. Tap OK.
    
24. To change your security lock type, from the DEVICE tab, tap Lock screen.
    
25. Tap Screen lock.
    
26. Confirm your backup password and tap CONTINUE.
    
27. Tap Desired screen lock type, and follow the onscreen prompts.
    
28. To learn more about requesting a device unlock for your AT&T mobile device so that it can operate on another compatible wireless network, visit www.att.com/deviceunlock.
    Note: If your device is locked and is requesting a "PUK" code, click here for instructions on how to obtain your PUK or PUK2 code to unlock your SIM card.