How is it best to introduce a lead? Our 9 week old pup is now used to her collar but when I have tried to add a lead the first thing she does is bite and play with it. I have offered a treat and the “drop” command and distracting with a toy but after the treat she immediately goes back to chewing it. So I then removed it. I fear I have rewarded her for chewing rather than releasing. Any suggestions please ?