You'll have to wait until it gets re-filled a bit; not just by yourself but by other users as well (I've gotten to that point, donated a dozen of items, still had to wait quite a bit till I could dive again).
People seem to be not donating as much this past week or so, or there's just more diving since the price cap on donations was raised (I've been getting mostly stuff from the admin it seems - you can only get from them I think it's like ten times in a day, to get more stuff is dependant on how many other users are donating/diving)