I have a 1/2 hp Craftsman. When I push the remote it will try to close but at various stages 1/4, 1/2 and 3/4 way down it opens and then the light flashes 5 times. I have checked the laser sensors and they seemed to be aligned. One is a steady green and the other is a steady amber. I can close the door by holding the wall button until it is all of the way shut. Please help...I would rather not pay the astronomical fee of getting someone to look at it.