Beaking and biting, to different thing, one more way a Grey communicate with. When your beaked , your being told something, ie: stop/don't, more, yes, no, etc. To respond say something like "I don't like that!" "Okay" etc, never No or stop it...Immediately repeat the same jester with your verbal response, with time, the pressure of beaking will lesson, remember, when one bird beaks another, they only beak feathers, not skin. they must learn.....