Alfie is a sweetheart, but his biting is a bit of a problem. He bites when he greets people, ( tail waggy biting) he bites when he is excited generally, He bites particularly badly when I put his collar or harness on. Some of the bites are really painful and draw blood as he chomps down so hard. Any tips? Is this usual at this age ( 11 weeks ) ?

many thanks

Diana