if you hit the bolt hard when removing, i bet you smashed the treads, if you got a tap set that big, you could re set the treads, or maybe try a new nut.

maybe you could grind off the bad threads if they are close to the end. or the old try to force it on and hope it clears the treads for ya.

when you whacked the nut did you have the nut turned back on far enough so it sat flush with the end of the treads? if not you mashed the treads for sure.