Quick question guys!!

I hit my blades against the wall and when i went to straighten them out again, the flybar is very loose. It wobbles back and forth, how do I tighten it up. The blades are floppin all over the place. I tried tightening the little hex nut inside the blade grips but they just spin.

Any suggestions, It spinds up fine without the blades on and nothing is really bent.