One of the buildings I work in is built on a hill so the entrances are a bit confusing. If you’re coming from the north, the entrance is on the first floor, but if you’re coming from the south, the entrance is on the “Lobby” floor (actually the second floor). So I was getting into the elevator on the first floor as an old guy with curly white hair and a baseball cap was getting off. He muttered to himself, “Huh? Where’s the lobby?” So I said, “The lobby is upstairs.” He got back into the elevator and said, “Arigato. Uh…sank you,” and grinned all the way up.
Made my day.