faceguarding

[minnesota ref]

guys i'm not the one who wanted to call the intentional foul in the face guarding situation. I just wanted to know if it was an illegal screen.
again, A1 is dribbling and B1 is defending. A2 ,who is on offense, is actually in a defensive stance facing B1 keeping himself between A1 and B1. When B1 moves to his left then A2 moves along with him. A2 is not putting his hands in B1's face, and there is no contact being made.
whats the call?