Glo Screen glitches

Hi

I recently got a Kobo Glo from a relative which has some screen issues. I'm not sure what is causing the issue since the issue seemly appeared out of nowhere.

The screen looks like this:

I've tried resetting it, reconnecting the ribbon cable and cleaning the socket to no avail.

Has anyone had behaviour like this? It's the same area of the screen that seems to be glitching but it does work properly when the ui draws a dialog over it. Is it a hardware or a software fault? And is there any way to fix it?

Thanks in advance.