You have to be real careful with the spring loaded awnings. Remove the wrong fastener and you could get a face full of mounting bracket.
Usually the topper awnings have torsion springs on both ends of the roller. Get ladder and check the roller to see if it rolls freely (bad) or if it's just jammed (not so bad). Beyond that check to see if it's still under warranty.
Post the make and model of the topper will help. I have PDF sheets concerning installation and such details for the toppers on my coach which might be different then what Tiffin installed on your coach.