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Yeah, it's pretty common for this to happen, they are pretty fragile these days. But there are guys out there that reglue them.
Maybe an auto trimmer?
I have done a couple myself but they never seem to turn out 100% perfect. I used spray glue that you can get from clark rubber or similar to stick them back up. But I also took the whole headlining out to do it. Probably need some new lining and foam to look real nice though. And you need to scrape off all the original glue/crap off the cardboard in order to make it stick properly.