Why does my phone lock again after I input my pattern/pin/password?

[Android Central Question]

Whenever I input or turn on the pattern/pin/password function in my Samsung Galaxy J7 2016, the moment I try to lock my phone, it resets. Like after I input the password or pattern in the lock screen, it freezes for a few seconds and locks by itself. And the process simply repeats.

 

[B. Diddy]

Welcome to Android Central! Does it actually seem to unlock successfully for a brief moment (i.e., do you see the homescreen appear), or does it seem like it's rejecting your password?