Craftsman 1/2hp problem - door is reversing
I have a Craftsman 1/2 HP opener. When I try to close the door it gets to about 6 inches off the ground and reverses back up. Then the light flashes. I thought that this would be due to blocked sensors, but the sensors are clean with a clear, steady green signal light. I can "trick" the door into closing by hitting the wall button as it begins to reverse to stop it, then press again to get it fully closed. This doesn't work well with the remotes. I need help, please.