Why has my ipads screen glitched

Has the screen been replaced by a mobile phone repair shop? If yes, take it back to them for warranty.

Is there a crack on the glass? If yes, get the screen replaced. If the crack is in the inside layer of the glass it will interfere with the touch screen functionality.

In short, the digitizer touch screen needs to be replaced.

Here is where to buy the part:

iPad mini 1/2 Screen Digitizer

Here is a guide on how to replace it:

iPad Mini GSM Front Panel Assembly Replacement

Hot tip: When lifting up the LCD, use plastic money notes if you have it available, they are great for cutting the adhesive under the LCD. I use that to slide cut the adhesive on the top and side of the screen (Do not do the bottom of the screen as that is where the LCD black ribbon flex is).