Spinning Footpeg

A couple of weeks ago on a ride I noticed that my LHS Footpeg was spinning around in the mount so when I got home I got out the Allen key & tightened it up & added abit of Loctite, today while on another ride the same thing happened, so on having abit more of look at it I notced that the RHS peg would moved forward & back about 10 to 15mm but the LHS peg when tightened didn't move at all so I was wondering if I was missing somekind of spacer or locking washer that allows movement in the peg without it spinning right around or somepart of the Mount Bracket is missing because nothing seems to be broken off. Any help would be great, it's not the best feeling when you go to put weight on the peg & it just folds down, thanks. 
