Any hints on releasing the TT tongue from the ball???

Last time I was out, I watched my neighbor struggle with his hitch, trying everything to get it dis-engaged. Now this only applies to a hitch/receiver set up. He asked me if I had a floor jack to maybe get the ball to release....I said, "why not pull the pin on the receiver". He searched for his key , released the receiver and pulled forward with in his truck and the receiver/ball stayed with the trailer..his truck was free and after the pressure was released, the ball dropped right out.