My garage door opener failed with door up. When pushing button to close it makes a noise but there is no movement. Upon investigating, the opener lifted the door too far, hitting the stop bolt and wedging it. After unscrewing to releave tension, door functions again, but again does not stop where it should and hits stop. There is a green light visible on circuit board, looks like D12. It blinks 5 times and then repeats. Any suggestions would be appreciated. Merry Christmas!

Dan