We put liquid rubber roof on our 5th wheel approx. 5 to 6 yrs ago. Had covers on and off over the yrs with no problems. Came to Florida this year and the cover was 2 ys old and it was stuck to the tacky roof. We ripped the cover off with pieces still glued to the roof. After a couple of months we checked the roof and it is now back to normal. What happened? We want to get another cover but don't want to wreck another cover.