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

Replaced screen, now it flickers and tears

Hello. Basically my phone fell out of my backpack and had to have its screen replaced. Everything went smoothly, the screen works, it's just that sometimes it flickers and I cannot understand what is causing it. It happens on some album covers, when i drop the notification bar, or when viewing photos and such. The video: https://www.youtube.com/watch?v=hFp2pkGPo5k Is this something that can be fixed or am I royally screwed? Thanks. :)