My toadstool got mad at some point (after I had it for nearly a year and it had been happy in the same spot) and shrank up and looked like it was dying. I wanted to remove it from my tank after it looked this way for over a week (due to the bad nutrients that it would add to the water), so I tried to pry it off the rock. It was tough to do and I moved my whole rock pile in the process, even though it was on the bottom rock. I finally got the main part to let go and put it in a frag basket just to make sure it was dead (I figured, if it wasn't already, I just did it in by abusing it!). Don't you know, it popped right open the next day! I superglued it onto a small rock and placed it in a new spot and it looks great now. Don't give up on yours. If you can move it, try a new spot...there may be something where it is now that it doesn't like.
Good luck!