This service dog just wanted to play catch in the garden with its owner, but the closed door was blocking its way – or so it thought.

Luna, a Belgian Malinois mix, stands in front of an open sliding door at a home in Hamilton, Ohio, seemingly thinking that it's closed.

"The door's open, silly!" says the dog's owner.

But Luna only realises once the door slides shut – much to her amazement.

Once Luna realises, she darts out onto the patio.

The clip was filmed on June 21.

Luna is my psychiatric service dog. We live in Ohio. This was after Luna had, had a full days work while we were visiting my mother. She was not used to using sliding glass doors and couldn't quite figure out if it was open or closed.