Man it happen cause screen is damaged buy a new one but the price got higher recently

You gonna need to buy a new screen

This happened to me once...had to change the screen

Its probably because the screen has been crashed.

There is a clip-on YT search it. If the problem is not very dark take a pen or some pointy material press the affected area gently, please don't fear it will make it worse 👍🏾 😁😊🙏🏾. Bye 👋