Actually, the whole point of an invisible fence is that the dog is afraid of the potential for pain (the shock) to the point that they won't run through the boundary.
As you've unfortunately discovered, a sensitive dog - or in your case puppy - can be traumatized to the point of shutting down. Please reconsider your containment options & throw away the electronic collar. Put up a real fence, or take the dog out on leash. Even using a tether of some sorts is a better option to terrifying the poor dog in her own back yard.
As you've unfortunately discovered, a sensitive dog - or in your case puppy - can be traumatized to the point of shutting down. Please reconsider your containment options & throw away the electronic collar. Put up a real fence, or take the dog out on leash. Even using a tether of some sorts is a better option to terrifying the poor dog in her own back yard.