I have a GMT900 Suburban that I purchased recently. It has the 60/40 bench seat in the 2nd row and then the 3rd row split 2 seater bench seat. One seat in both rows will not fold forward/flip forward. The back will fold down, but the seat will not fold forward. They are manual seats, and I have tried pulling up with force on the handle and they still will not flip forward. The other seats that do work dont require much force applied to the lever. I am not sure how to troubleshoot or repair. Anyone run into this before?