Bamabreeze

3-15-2024: My 2019 GMC Sierra started with this issue several months ago. Problem was very intermittent. Some days it would alarm for up to 30 seconds. Other days never had an issue. After lots of research and seeing many comments I solved the matter today. under the steering column is a small switch which should be closed when the shifter moves to mark. This switch seems to be made of the cheapest parts available. Remove the 7mm bolt under the column. Turn steering wheel to the right and you will see a 2nd 7mm screw. Then back left and remove 3rd and final bolt. at this point you can pull out the bottom half of the steering column off exposing the switch. You will see 2 black wires connected. I soldered a small jumper wire across the 2 black wires. put everything back together. 45 Mins including a test drive. Problem completely resolved. if you wish to order a replacement part another posting listed it as. GM 84800776. I have not verified the part as accurate. Good luck with your repair.