Where are you located? Perhaps there's someone from a local fleet who can help you.
My guess is that for some reason you are unable to hoist the main that extra inch or two that it takes to get the halyard ring above the mast hook.
You also have to rotate the mast in the correct direction to get it out of the hook. I have a Hobie 20, and in my case, I rotate the mast counter clockwise to get the sail down.
The drill is:
1. Hoist main an extra few inches.
2. Rotate mast counter clockwise.
3. While mast is rotated, pull down on sail, and it should come down, and miss the hook.
If you rotate the wrong way, you could rotate it almost backwards and not get it out.
It may also be that something is fouled up there, and you may have to flip her on her side. An additional suggestion is that you get an aussie style ring, which is a twist shackle welded to the halyard ring.
Good luck! I feel your pain!
Sea ya,
Tim J.