Why does my S9+ shut down when i lock screen?

[Promoe fan]

Ok so, i know this is stupid, but i rooted my phone to make it a bit more exciting. And, it works ALMOST fine... exept, when i turn screen off, my phone kinda just turn black. And i can't startbit up unless ibuse Volume down and power button for a few secs. It doesn't happen if ihave spotify running with music. But im thinking to unroot it and make it stock again. idk if that would help, but how do i fix this pls.

 

[Rukbat]

It won't restart with just the power button? (If you have AOD disabled, it should turn black when the screen is off.) Also, which lock screen do you have it set to? None, Swype, which?

 

[Promoe fan]

The lock is just a pincode so far, and no it wont restart with just the power button. And AOD is disabled, its like it freezes when i turn off screen, so it stays black till i use the Power+VolDown for 10 seconds.