Alko wheel lock

Hi one and all. I have a problem with my Alko wheel lock in as much,  that when tightening the bolt into the receiver after about 3 turns it becomes very tight and impossible to turn any further. I have tried another bolt of the same thread with exactly the same result. I have no recollection of damaging or cross threading when tightening in the past. I have been told by a couple of people that Alko have a tool, a tap and die I suppose, that they loan to recut the thread in the receiver, I have contacted Alko by E mail but have yet to receive a reply. If any member has any information on the subject I would really appreciate it.