@Boudicca908
The man made mounting material or as I refer to as PVC, does not hold screws or threaded fasteners very well when using the same size fasteners as were original installed. I would suggest removing one of the existing screws and then finding the same type of screw that is one size larger. I think they are common pan head screws and installation and removal can be accomplished with a Phillips screwdriver. Some type of adhesive may help, but anything like epoxy may make removal difficult. So if you do use an adhesive, use it sparingly. You can always add more the next time.
Mossey