Main Flex Cable Replaced And Brightness Problem

I replaced Main flex cable because of microphone is damaged.
Now my screen brightness is always full.
But I can adjust the screen when I try to use app
I tryed hard reset and the other ways
İ couldn't screen brightness off when I try to use normal conditions. I can just adjust to screen
But when I use *lux * app
It is working
And I can adjust my screen brightness whatever I want