If he's your first dog, 3 weeks might seem like a long time for him to get it right but it's really not. Please be patient with him. Yorkies can be very sensitive so this being his 3rd home might contribute to the potty issue. Is he neutered?
I agree with the other members advices on playpens and crate training. I'd also like to add that you invest in a spot cleaner like bissel's spotbot. Patience and consistancy is the hardest thing. I hope things will work out for you and your new furry family. |