I used solar heat, peeled them off, then a microfiber cloth with some acetone on it, then washed off with soapy water and waxed. No side effects after 2 years.
FWIW, mine still works 1026 model with Iphone 12 Mini latest IOS.
Have you tried doing a factory reset on the head unit and re-setting up?
Is the free level of On-Star still active? (Clue if its something specific to your car....)
Old,, but who knows if someone gets motivated.. :) I would think the more likely option would be to rebuild the stock charger with heavier parts, use a programmable controller out to the car so it thinks its charging as designed? But actually charging at a higher rate.. Or It would not surprise...