tas several members have complained here of poor, thin material in the seats and and doors. And have had theirs fixed under warranty. Take it to the Dealer and tell them it needs to be fixed. If you cant get them or gM to foot the bill (stance is everything my friend, get tough) here is a copy paste I did for another member......
I had a crack in the leather of one of my seats. It was apparent that it was cracked and not scratched. I had a bit of a yelling match with the service manager and they replaced a panel in the seat. When I took the car to the place that repairs leather seats they commented on how cheap the leather on newer vehicles are. I was told that it is not uncommon for leather seats to prematurely crack and they had a 2006 GMC Sierra in for the same reason (with 1000 km).
As Venom pointed out make a fuss and I am sure you will be get your door card fixed under warranty.