Removal of Timing belt cover

So I need to get my value cover off but first I need to remove the timing belt cover. I've removed the two bolts at the top then start undoing the alan key bolt half way down and it gets to a point where it starts clicking and spins! Any suggestions? And I hope that makes sense lol

It should just come undone but by the sounds of it someone has wreaked it…
Can you pull it out?
Does the bolts spin or is the clicking from the allen key spinning in the bolt?

Have you got it loose enough to get a bit of leverage behind it - not to force it, but a little pressure might help it re-engage the threads. If I remember rightly that bolt isn't very long, so doesn't take much undoing.

A slim dental Pick on the under side of the head can help you pry out while turning out the screw if it is stripped.

But it sounds like the bolt is out, but the cover isn't loose?
Try to pry the bolt as the bolt may be out, of the internal bracket, but not loosing from the cover.  This can prevent the cover from coming off.

Taking off the alternator belt can also help as it can get in the way when removing the cover.

It's been a couple of years since I removed mine, but I seem to remember that the Allen key bolt fitted through a rubber grommet and that itself can hold the cover quite tight, so needs plenty of giggling around like others have said.