alns-rx7

I have an 88 rx7 with the glass sunroof. I used to keep it in the vent open position all the time and one day when it was getting cold I went to close it and it was stuck. I could see it try to move just a hair but then stopped and was stuck. I had a guy that fixed leaky sunroofs a few years ago mess with it and he got it closed, but it is still stuck. It is also now leaking if it rains. Any ideas?