I was just trying to add to Arm Guards to my Shared Bank and it said there wasn't room. It was full (100/100) but I did have some Arm Guards already in my Bank. Since they will not be taking up any more space (just adding to what is already there), shouldn't I be allowed to do this? When I remove 1 item (99/100 items) , the Arm Guards transfer works like it should and, at the end of the transfer, there is one slot free. Apparently, if the Shared Bank is full, you can't add to an already existing Pet Gear or Food Item.