During a game my left flipper all of a sudden was misaligned with the right flipper and now is very weak when striking the ball. I removed the glass and noticed that the flipper is able to bend forwards and backwards very easily and locks in a new alignment. It kind of reminds me of when a screw is striped and never becomes completely tight. How can I lock it back into place so it's tight? Any suggestions on how to fix this problem.

Turned out to be a broken flipper. The machine has the clear flipper mod that is cheaply made. The right flipper is cracked but still functional. I like the look of the clear flippers during Klingon multi all so I opted to buy four extra flippers from Bay area for around $4 dollars a piece. Cheap and easy fix.