My 2019 Tahoe just started doing the same thing. Sat for a week or 2 due to Covid and I had the doors open a bit while doing the window trim blackout. Thought it was just the doors being open a lot and not being driven. I drove it 5 miles to Publix turned it off and then it was dead. A friend came by and jumped me and I went to Auto Zone where they said the battery was fine. Parked it at home and it has been hard to start or barely starts each time. Gauge reads 14-15 while running. Maybe I need to have the battery checked again?