Hi, our boxer Neo has had the problem of biting at ankles when guests and even us at home try to walk around the house. We have taken him to obedience school and work with him daily, however, this problem is getting worse. He is actually biting now and not just mouthing. Does anyone have any suggestions on what we can do to break this bad habit? He is almost a year old and a very large boy. He thinks he is playing, but it is not considered playing to whoever he is biting.