This is from one of my sources !

To permanently fix the headliner, go to your local auto body paint
store and get 3M 8088 spray adhesive- it comes out in a spiderweb
pattern.

Remove the headliner and fabric from the car.
Clean off (stiff brush) the cardboard liner and the fabric.
Spray the headliner and the fabric, one section at at time.
Press, roll the fabric back on the headliner.
Put the headliner back in the car.