Hello! I'm struggling a bit with my dog. My dog is trained to do several things, but the most useful is item retrival. If i point at something, and he can fit it into his mouth, he will bring it. The issue is, once he gets to me he'll just drop the item, unless I'm standing and he puts his front paws on my stomach so that his mouth reaches my arm. My struggle is, I'd like him to stand in wait for me to grab the item he has retrived, but he doesn't understand. Any tips?