The roof liner inside my A4 is seperating from the roof. Anyone ever fixed it?

The cloth material is seperating behind the sun visors and on the 2 corners in the rear. Kind of sagging like an old lady's breast. It seems like some spray glue will do the trick but I want to know if anyone has some experience with this kind of thing.

 

spray glue works but its messy, if you can pull the material down so you can get at the part that's sagging then use brush paint on glue and ensure its clear colour glue

 

so how wold you go about removing your roof lining because I have this same problem but it's a lot worse than just a little bit in the corners