please help with potty training!!

Hi!! I recently adopted an 8 month old puppy! We've had him for 3 months now and I was struggling in the beginning but he has become the best boy, he is so so smart, does incredibly well when I train him, he has learned so many tricks, does good on lead, everything! But I can not for the life of me fully potty train him…

I've done all the tips and tricks, we take him outside as soon as he wakes up. We go on a walk, eat/training session, then another quick pee and then he will usually sleep through the morning, wake up at lunch time, another pee, then I have lunch, he has some play then he has lunch and another training session, another pee and he will sleep or be settled most of the afternoon, then comes the bad part, he will wake up all excited at about 5pm, but we usually wait for my dad to come back home, which is usually at about 8pm, for his last walk of the day. In these few hours, he will ask to go potty like 10 to 15 times (he goes over to the backdoor), I try redirecting him or ignoring him, sometimes I feel like he just wants to go to the backyard, but as soon as he is out of sight from me he will pee, and if I take him outside he does in fact pee, even if it's for 2 seconds, he does a pee. But obviously he doesn't have to pee, I kid you not there have been times where we come back inside from a pee and he will ask to go back out 1 minute later!!

Some people have told me that this is just cause he is a tiny guy and can't hold his bladder still, but he holds it well through the night and if we crate him through the day, so I don't understand where this behaviour comes from, it feels like when he's bored and doesn't know what to do, he pees.

I try to keep him on a schedule and give him lots of praise whenever he pees outside and in the timings I want (less praise when he pees outside of that timing), when I take him to the backyard I have a designated spot where he goes, I wait for 2 minutes, and if nothing gets done we come back in, and whenever we go to potty I don't play or even speak much outside of saying "go potty". I don't know what I might be doing wrong or if maybe he really can't control his bladder still and I'm worrying over nothing.

If you have any tips or anyhting please let me know!! this is so frustrating, I feel like if I could fully rely on him to not pee inside I'd be so much calmer and looser with him, not constantly needing to check on him or have him be around him, I feel like it's taking over my everyday constantly looking at this pup to check his not peeing…