I have put multiple things up on the auction house, and when they expire because no one bid on them, there are two options you can do to these items: you can either resell them or deposit them back into your shared stash. The first few items I tried to resell, but when i click the button to do so the buttons gray out and a notice below the item said available <1 m or something of that nature. After about 5 or 10 minutes it pops back up as available but gives me the same two options: Resell or deposit back into shared stash. It was a little frustrating at first becuase i wanted to explore the AH a little bit more in depth but couldnt because I had to wait for these items to reset so I could deposit back into my stash and redo the whole process of selling again from the beginning. I'm assuming this is a bug that is well known but i could not find any existing threads about this specific issue, so hopefully this is of some help to you blizz guys!