Next pull on the screw with a pair of pliers.
How to repair dents in aluminum siding.
Hopefully the dent will pop out and the siding will be good as new.
Fill the dent with the two part auto body filler.
Drill a couple of 1 8 inch holes in the part of the siding that contains the dent.
Drill a hole in it drill a small hole in the center of the dent.
Use a putty knife to scrape the surface level with the siding.
Place a flat washer onto a sheet metal screw and then screw it part of the way into one of the holes you drilled.
Sand the patch to remove all roughness and paint it to match the siding.
Using sandpaper take off all the paint.