The only way we taught Bonnie to stop biting was to leave the room every time she did it. She was really bad and even used to try jumping for my face with teeth snarling
I was convinced she was a vicious dog.
'No' didn't work, sleeps didn't work, ignoring her or turning our backs didn't work. Leaving the room did. It took time and some days we were in,out,in,out,in,out. Only for a minute at a time or less but she eventually clicked that if she bit us we left. Once we went back in, we always made a fuss of her and if she bit us again, we left immediately. So wish we had recorded us as we must have looked hilarious with all 3 of us getting up, leaving room, waiting behind door then going back in, every few minutes
She is now 14 months and the softest, silliest and still nuttiest girl around who will snuggle all day long. Not an ounce of viciousness in her. Its hard work but worth it xxx