Touchscreen not responding after a few minutes

Hi everyone,

I am having a little issue with my Redmi 7 that I couldn’t solve yet.

Basically, after few minutes of using it, the screen’s colors suddenly change, as if a greyish filter was applied, and the touchscreen does not respond anymore, except for the three buttons on the lowest part of the screen (home, return and windows). I must lock and unlock my phone to make it work properly again.

I was wondering if anyone had a similar issue and managed to solve it without restoring the phone to its factory parameters. I have tried to reboot it in safe mode to see if it could be caused by an app but it wasn’t the case. The MIUI version is 11.0.7.0.

Thanks a lot,

K.