Just new to camping and pop ups. Bought a used 2009 Jayco M-1206 popup trailer this spring and finally am taking it out. Set it up this past week in a parking lot; lowered it by crank and it wouldn’t go down the last inch. Pressed it down and continued to crank. Tried to raise it up; crank froze up. Can’t get it to move. Don’t want to force it. Help?