My three month old puppy won't walk on a leash, as soon as I hook her leash up she just ducks and stays close to the ground and even tries pulling away sometimes. I if carry her away from the house and put her down with the leash attached she will go back to the house but that is the only time she will walk on the leash. I have tried giving her treats every couple of steps but it doesn't seem to work. I left her leash hooked up and let her walk around on her own and she has no problem with that, but as soon as the other end of the leash is in someone hand she won't move. What should I try or what should I do to fix it.