The person obviously isn't happy or they wouldn't have brought it to me to be fixed.
To be fair, you didn't identify this as "the reason it was brought in." I've ended up fixing things not originally requested (after clearing same with customer, of course) and most of my home service visits involve fixing the problem the customer identified along with about 20 things of the "while you're here" variety or that I consider to be in the "must be fixed" if they consent but didn't even know about (e.g. unsecured WiFi) category.
From your description I would suspect something's gone wonky with the LED display, but, as Platypus has previously requested, a photo of same showing clearly what's not working, and preferably a full screen photo, would be most helpful in making a definitive diagnosis.
Brian AKA Bri the Tech Guy (website in my user profile) - Windows 10 Home, 64-Bit, Version 1803, Build 17134
Memory is a crazy woman that hoards rags and throws away food.
~ Austin O'Malley