Genie garage door will open but you have to hold the on for it to shut. whats wrong?

make sure your eyes are lineing up and the lights on them on. On genies they are red. If they are aligned then chances are you have had a power surge or lightning strike. In which case you might need a new circuit board. I wouldnt invest fifty cents in a genie, they are nothing but junk. I would recomend either go get a liftmaster or craftsman, or any thing by chamberlain