puppy peeing all day

Hi everyone! My partner and I adopted a puppy about 6 weeks ago now. She is 5 months old and will not stop peeing like every half hour. I feel like I cannot focus on anything because every time i look away she has an accident. We’ve been trying to potty train her, and she finally understands that when she goes outside she needs to go to the bathroom, but twenty minutes after peeing outside she’ll leave a puddle on the floor. We’ve already taken her to the vet, and after hundreds of dollars in sonograms, urine testing, cultures sent out, they found absolutely nothing wrong with her. I’m just at a loss, i have no idea what to do. And I know she can hold it because she doesn’t pee the crate overnight or when we’re at work.