Once it starts to degrade and come away like yours is, there'* no real fix. You have to purchase some new liner, it'* not that expensive. It'* very simple to do too. It took over 20 years to come off for my Firebird. With that car the whole ceiling panel can come out the side door. I don't know about the 4-door Bonne'*. They may not have enough room, with a center pillar post, so maybe you would have to take it out thru the windshield. Beomes a much bigger job.