Mob attack condition

I tried to make a mob that attacks the player only when the player isn't wearing diamond armor, but it attacks me no matter what. I used the "attack (in sight only) (nearby only) entities of type" block and set it to "EntityPlayer". I made this procedure:  and set it as the condition for the mob on the attack block both as "additional start condidtion" and "additional continue condition", but, as I said, it doesn't work. Can someone help me?