Epix (Gen 2) Phantom touches 17.28

I have had a Garmin Epix Gen2 for about 2 months, and today I started experiencing “phantom touches” every time I turn on the touchscreen. The device has become completely unusable as these touches occur every 1-2 seconds.

There is no screen protector on the device, and it hasn't suffered any hard physical damage, so it doesn’t seem to be a hardware issue. I have tried a hard reset, software reinstall, Garmin Express, and the 30-second on/off trick, but nothing has worked.

Does anyone know what else I could try?

Software Version
17.28