My bench seat is starting to fall apart in the back. There is a plastic panel that goes across the seat but is cut out where the armrest would come back. There is also plastic, like a garbage bag type plastic, coming out from under it, and it looks to be tearing out. I want to know if the plastic panel on the back of the seat is suposed to go all the way across the back of the seat over the armrest opening. Has anyone else had a similar problem with their bench seat?