Display Brightness and screen bug

After changing display i got some issues. One of which is provlem with aux and thats why i had to open it again.After that opening i received ANOTHER glitch, which makes the phone to randomly change brightness to max while also showing black screen with the clock on the top right corner. Also when the phone is off it randomly turns off and shows the same black screen and logo. I will post picture of it.Help pls because after this i opened it again and coudnt find what is causing the problem.``

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