Hitch will not come off the ball.

I purchased a new TT mid December. Got it home the same thing happened to me, I called the dealer , they sent a service tech he was unable to get it loose. We had to remove the hitch pin ,get the truck and the trailer level, chock the wheels and pull the truck away slowly. He said he had never seen that happen before. When I purchased the trailer I also purchased a high dollar sway hitch with it. There was a adjustment on the hitch itself that had the ball slightly tilted toward the front of the truck and after moving the trailer it put everything in a bind. They adjusted it, I hope it works haven't had the weather to try it yet. It sure made me feel stupid when I was unable unhitch it but better in my yard than a camp ground. Hope this helps.