So I took my chain guard off, and now when I go to put the rear bolt in it just spins and spins and I can pull it straight out. The threads are still intact, and I even got a new bolt from a bike shop but it just doesn't work.

Has anyone else had this issue?

Aye, needs a Helicoil or revitting to bigger bolt but thread lock seems to have worked so far.

Rethreading not revitting.......................