My Harley is a 4 year old rescue from a puppy mill we have had him for 5 months. He is potty trained to go outside now but as soon as we leave the house he will poop in front of the door. we have tried putting him in a crate and he does well except for when we leave the house even if it is only 5 min he will poop in the crate.( we always take him outside before we leave) any suggestions?