The rule says that a player must be covered by two players (one of them is always the goalkeeper).
In this case the keeper is out of his post and the player receiving the ball is covered by only one defender.

What I don't understand is how stupid the AI is and your player decided to pass instead of shooting in the empty post and scoring an easy goal. The same goes for clear one to one chances where the attacker goes straight into the keeper and loses the opportunity to score.