Foreign language film about a man that fakes dementia

I saw a movie on a plane in late 2019. It was a sub-titled foreign language film (maybe Czech) about a man who faked dementia as a way to leave his wife. He moved to a hospital/ asylum that was run by his friend, meaning he could leave whenever he wanted and return when his wife visited. Until the manager was changed and he had to come clean and prove he wasnt crazy.

If anyone can help with the film title that’d be great! Thanks