Yes this happend to me. The stud that you are screwing the nut on is welded to the inner wing from behind and has unfortunately broke free of its weld so when you turn the nut it just spins. The only real way of fixing it is by re-welding it. If you remove the interior carpet over the wheel arch you'll see the two ends of the stud and it's easily welded again or if your lucky you can grip it with some mole grips and tighten the nut. I found re-welding it to be the only way
