I built a dog run for my dog to do his business in so that I don’t have to walk him every day, but he will not go to the bathroom in the area. The only time he will go out there is when another dog is out there with him. When other dogs are not around he will not go to the bathroom out there. We have brought in outside rocks he usually pees on. I have also put sod and other types of surfaces out there to get him to go , but nothing has worked. Once I bring him out side the fence or to the front of the house he has not problem going. Please let me know if there is something I can do to get him go out there.