With the garage door insulation kit shown in the pictures, one clip gets bonded to the door, and the other engages it after being pushed through a hole in the insulation.  The clips supplied in the kit can warp over time and disengage to the point where they start to fall off.

When that happens, discard the outer clip and slide this replacement on. You may need to move the insulation out of the way a little to ensure the clip has enough room to push all the way in. If the original clip prongs are highly warped, you may also need to pinch them together enough to get the replacement clip started. Push it on until you hear it lock.

Parameters I used:
Material PETG
Layer Height 0.20mm
Perimeters 4
Infill 15%
Supports: None
Nozzle Diameter: 0.4mm