This is one of FIFA rules on hand ball.emphasis on the final line

A handball should not be awarded if a player is ruled to have handled the ball accidentally. This refers to a player either attempting to protect himself from injury, for example by placing the hands in front of the face and then being hit by the ball, or a player being hit on the arm by the ball without moving towards the ball and without being able to move out of the way. An example might be a snap shot hitting the arm of a defender at point-blank range. However, if a player’s arm is in an unnatural position, for example outstretched or above their head, then a foul should be awarded whether accidental or not.

who be this one?