vehicle stuck in reverse after shifting to drive

On Sunday I was at a flat dirt lot at a boat ramp... after my fishing trip I hopped into the car put it in reverse... backed out of my spot careful to look behind at all the trailers around me... stopped and shifted into drive... the backup camera turned off and the D lit up on the dash... I stepped on the gas and the car went in REVERSE... right into an empty trailer I had been so careful to avoid in the first place. Thankfully no damage happened to the truck towing the trailer or the steel framed boat trailer itself, but I have a large dent in the bottom half of the bumper. I took it to the dealership and they had it all day on Tuesday and couldn't figure out what could have happened. So basically I am stuck with a large dent and no fix... Then this morning (Friday) I backed out of my parking spot at home... again a flat lot only this time its paved... and after shifting into drive it again was stuck in reverse... I had to stop put the car in park and then shift to drive to get it to work. Super frustrating!!!!