Two place trailer, came off the ball I was towing our two place trailer with two Sparks on it today. We went a large bump in the freeway, I saw the jet ski's and trailer get about 6-12" of air. Next thing I know, the trailer is fish tailing. I safely got pulled over, figuring i had a flat tire. Nope, the trailer came off the ball. I had to remove the hitch pin and unlock the coupler to get it back on. Thankfully the safety chains held up and nothing was damaged, besides the skid plate on the front of the trailer, it is scuffed up and shaved off some metal. 

This was the only times I can remember, not pulling up on the trailer after hooking it up. Did i just mess up and not get it connected right?