NO crickets! How much handling are you doing? Does he have hides? At least 2, one on cooler side & one on warmer side.
Did you briefly but adequately warm his f/t rodent right before offering it to him? BPs rely on their heat-sensing pits to recognize their prey- they're not into cold food.![]()
And HOW you offer his food matters greatly also- BPs are shy, ambush-predators- they prefer to eat in evening hours, not under bright lights- in a quiet room, some privacy...& if you add motion to their prey, a little goes a long way, & a lot of motion is apt to turn them off.
Prey should not appear to approach the snake, okay? (they don't do that in the wild either) Some snakes will only eat motionless prey, also- what have you tried or not tried?
Offering too frequently will just stress them further into refusing. Offer once a week (& not at all if they're in shed), not more often than that. Do you have feeding tongs?