Idk, it sounds like your setup is fine. It never hurts to recheck those temps though. I've had BPs stop eating for 8 and 12 months before and they were just fine. If you think he may be ill, then take him for a vet visit. If he's just being a stubborn BP then keep offering food once a month until he decides to eat. I've always had the mindset that any animal will eat almost anything if they're hungry enough. I've never seen a healthy animal starve itself to death when food was available. Best wishes and I hope he eats again soon.