“If you’re doing isn’t working, try something else, possibly a new play group or school o asdfadsf ”

If you're doing isn't working, try something else, possibly a new play group or school or therapist. He's old enough to respond to self-interest. Instead of saying because I said so, explain how he benefits from behaving well. It may not have occurred to him that he can control his emotions. Above all, don't punish yourself. You deserve love.