Adaptive brightness is enabled even after I disable it

[AC Question]

I have a BLU studio x plus and recently the screen has started flickering slightly. After messing around with the phone settings I discovered that the adaptive brightness had been enabled. Every time I disable it, it eventually becomes enabled again without me touching anything. What causes this and how can I stop it?

 

[Tim1954]

Is this adaptive brightness from your screen settings or auto brightness from the pulldown quick settings?

 

[Tameon7]

It's from the screen settings.