I had a similar problem with my 2014 CMax Energi. I am at 58K miles. It had been 100 degrees that day with car parked and windows may have been closed (I thought I had them open a crack. I loaded the car with groceries from Costco. It was heavy and I put the seats down. I traveled 175 miles. It was cooler at my destination - usually 80 - 90 max. I tried to put the seats up several days later and couldn't. I discovered that the seatbelts were jammed and caught on the seats (see attached pics). I was able to unstick them and bring the seats up but they no longer work. Note that they look like the plastic melted. The dealer has ordered new seatbelts and he said they would "probably" be covered due to the fact it is a safety issue and it doesn't look like there was unnatural abuse (the surrounding seat was not damaged).
