Solved! 6.0.0 Deep Sleep Problem

Solution
I am not referring to just 'stock' apps. Any app can keep a device from sleeping and drain your battery if it is set up incorrectly (or intentionally to do so) by its creators.

smhgs92

Prominent
Oct 8, 2017
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510


I checked the "Display" settings, "Sleep" is set to "After 15 seconds of inactivity".
About the apps that may keep the phone awake, the battery stats screenshots I posted is from "Safe Mode", only stock apps were running.
 

smhgs92

Prominent
Oct 8, 2017
3
0
510


Yeah I got your point, what I'm trying to say is, it was on safe mode, so if it's an app problem it has to be a stock app because only stock apps are allowed to run in safe mode.