P20 Pro - 9.0, Background app problem

[draligus]

I have p20 pro with android pie.
I have made all battery saving settings.
But, all background apps are always active.
This causes battery drain.
I have blocked background activity from settings menu..

P. S. :
I have installed firmware via SD CARD, twice.
I have made factory reset.

 

[draligus]

I have attached screenshot...