Hi. I think of myself as an expert in this matter. Call me a connoiseur of pee. Hee Hee. Some of these things you may already know so sorry if I'm telling you stuff you already heard.
1. Of course, there could be a urinary issue like a mild infection or something else, so first I would bring Cody to the vet to make sure.
2. Backyard breeders or a registered breeder for that matter could be completely lying to you. Some of these people are such good liars, they believe it themselves. Once they are finished with a dog, they will say anything to make you adopt them. Some breeders treat their dogs like cattle. They are not pets, or trained whatsoever. They are kept in crates all there life either inside or out and they have little to know people experience. Now I'm not saying that you're breeder was like this but it is something to consider. The jack russell terrier breeder in my home town had tons of dogs in crates and the dogs were not trained whatsoever.
3. Clean the affected spot with pet stain remover. I'm sure you've heard this but it's super important. Mr. Clean or Lysol is made with ammonia which smells like pee and they will keep peeing there.
4. Don't clean up the pee when your dog is watching. I find it funny but it could be true.
5. Put the dog out after eating, sleeping, and playing.
6. My Saint Maxwell took 7 freakin months to properly house train. It finally just clicked in his head and he hasn't had an accident in a long time. (Well, at other people's houses he has had accidents but it's a bit of confusion I think on his part.) My cocker took like 2 weeks to be trained and he was only 10 weeks old. Some dogs learn quick and some don't. We did the same things for both dogs so it wasn't a matter of consistency either. My Saint was just slow to learn. My friend had max's older brother and her's was the same thing. HHHUUUGGGEEE Puddles.
7. Try to restrict his mobility during periods of alone time. I baby gate Maxwell in the hall sometimes at night or when working. They don't like to pee where they sleep. When he sleeps in our room we can hear him ask to go out so there's no problem.
8. Maxwell would not bark to go out. He knocks on the patio door with his paw. I've heard that some people hang bells on door knobs that the dog could jingle. A lot of people don't like the fact that their dog asks to go out and they think that dogs shouldn't and should only pee when they are allowed to go out. Personally, I don't follow that philosophy. I wouldn't want to be told when I can go so I don't expect my dog to enjoy that either.
Well, that's all I could think of as hints. I hope some helped.