mine does this all the time when it is too full b/c diapers get stuck on the other side. try opening it and seeing if you have some stuck ones too, and then empty the trash - or have your DH do it
This happened to me too....empty it completely and keep the bottom part open. Then push the foot pedal thingy, and it will make the spring on top go up a little so you can push the top back under it. You kind of have to force it, I was afraid I would break it, but it just snapped back in. GL!!
Re: my diaper genie is stuck open.