If you are talking about the butt stock, it is possible that the person doing the repair got glue or fiberglass into the action spring tube, blocking the spring follower. Another possibility is that he bent or dented the tube in the process of installing the buttstock, or installed some parts the wrong way.
If possible, I would take the gun back and tell the gunsmith what happens and that it appears to have been the result of the stock repair. He should fix the problem free of charge. If you want to try yourself, remove the stock and see if the bolt will operate and you may be able to figure out the problem.
Jim