So i have been teaching my puppy bite inhibition. So far it was going good. now im tring to get him not to bite at all or as much and he will growl at me lift his lips and bite me with aggression. ive tride time out, and he seams to keep doing. He also does this when i pick him up, and i understand that he might be doing it out fear of being picked up. I just don't know what to do. I don't want him to end up growing up and thinking this behaver is ok. His vet said to cover his muzzel and smack your hand. It doesn't hurt the puppy, but the sound will make him stop. I don't know what else to do. And yes ive done every thing possible that is positive reinforcement. Even putting a toy in his mouth and he will just drop it and go back biting.