Atwood bought Fantastic fan last year then closed the Michigan offices, warehouse, and production facility. I think I recall that the products are now stocked in LaGrange, IN. Looks like the end of one of the best customer service programs in not only the industry but in the country !
Now back to the issue--- Gently pry up from roof side with someone inside putting gentle pressure on the knob manually. Remember to pull knob down to disengage from motor to spin manually. I cleaned and coated my seals with baby powder each spring and no more sticking. Silicone works also but I had to retreat every few months if I started to get a slight stick.
Randu