My current Siberian puppy did this after about a week with us - at first he was doing great with house breaking and then he started to test his boundaries. It didn't help that we had a huge dump of snow and temperature loss and he had no interest in going outside as he was so young (the "breeder" gave us the option to take him at 5.5 weeks of age, or she'd sell him to someone else despite us already paying a non-refundable deposit). Basically the only thing that "cured" this was forcing him to go.
We broke his favourite treats into small pieces and would give him 1 when he went out the door, 1 right after he did his business, and 1 when he got back to the door. Within 3 days he figured it out and stopped having accidents - assuming we picked up on his "cues" to need to go, and took him outside accordingly.
He's a very high energy dog, and gets easily excited with a lot of people around and will often slip off into an empty room to relieve himself then join back in on the fun - so the easiest way to potty train him has been to continually take him outside and pay close attention. He will start to walk funny, and sniff the ground following scent trails. I also know that as soon as he wakes up from his Nap, he has to go and he does "#2" twice after each meal. The first one usually happens roughly 45 minutes post-eating (depending on if he's been playing or sleeping), and then again another 45 minutes later. He, of course, drinks when he eats thus needs to go pee within 10-15 minutes. The saving grace
primarily has been feeding him on a schedule rather than having food out at all times.. this way we can time roughly when he needs to go, rather than not being sure if he ate, or didn't eat. The "breeders" always had food out for them (but they stayed outside almost all the time as it's much milder where she lives), so we opted to feed him 3x per day.. 7:30AM, 12:00PM, 5:30PM. His breakfast is his largest meal of only dry food + boiled egg, lunch is small in terms of dry food but includes his Raw/Wet with the dry, and his dinner is medium sized of dry food.
Hope I've helped some
Puppies can be tricky, and everyone is different. The one I have now specifically, rarely asks to go outside - it's a matter of reading his body language. Others are more vocal about it