Hi i have had birds all my life and it sound like the i have to be the boss stage when he bite say no sharply and genly tap cross the beack then wait 2mins if he bites agin do it gain and gain till he lern biting no acceptal i have done it with cockatoos weerios and a couple of bugies and remember when he dosen't bite u prasie him immerdely as it renforcing that he will get hit if he bite and praise if he good and he bound to want prasie hope it helps
Amy