I have a 2019 1500, 3 days ago I went to start my truck using remote start, it wouldn’t start so I got in it and it still wouldn’t start. I ended up jump starting it and the service engine light was on. I immediately took it to an auto parts store to have the battery tested and it showed to be good. They ran the code on the service engine light and it said replace transmission gearshift assembly. The service engine light went off the next day and I didn’t have any problems with it starting until this morning and I had to jump it again and the service engine light is back on. When running the battery voltage reads 13.9 and when not running it reads 12.3. Any ideas on what could be causing this?