Android is crashing when screen off

[AC Question]

Hi, I have issue with my phone Leagoo Alfa 1. When I use any proximity sensor screen on and off app, my phone randomly turns off while screen is off.
This does not happen when I combo proximity app with keep awake app. But the battery drain is unbearable.
Is there anyone who can help me?
The phone is rooted with xposed framework, running android 5.1.