I was walking out with my dog and a family liked it. They said their soon going to be on heat and they where planning to mate her we made an appointment to the vet to see if there where any problems thanks god everything was just fine . They come to my house but my dog as if he wasn't smelling the on heat he smelled it a bit and come back next to me she was ready for sure cause she was posing in front of him with her tail up but he didn't take any notice of her my dog is 4 and a half years old what can the problem be ? Can anyone help me plsss