Crazy D axle nut loose.

So I have a Crazy-D that I was playing tonight, and after a few minutes of play the yoyo started wobbling extremely hard, and was unable to be touched to smooth it out. I picked it up and heard something rattling around underneath one of the caps. I tried taking the cap out, but couldn’t. Eventually I figured out how to get the axle housing out of the yoyo and saw that there is a nut that screws onto the axle housing and it had came completely unattached. It would seem that the only way to fix this is to be able to take the cap off, but they aren’t meant to come off according to the YoyoExpert store post. Has anybody else had this problem and been able to come up with a solution?