Whenever I am about to walk my dog, he likes to get up on two legs with his two front paws on the door. He then proceeds to muzzle the doorknob and then look at me waiting for me to open it. He knows that is where the door opens from, but he has no way of turning it. One time however, I left my dog roam free while I went to the store. When I came back, I couldn't get into my apartment, had to call maintenance to break into my own apartment. Turns out my dog had figured out how to lock doors. At some point while I was gone, he must've heard a noise outside. Doing his usual routine of front paws on the door, he must've accidentally (or who knows, maybe intentionally) locked the second lock. It was a weird exchange with the maintenance crew telling them my dog had locked me out.