Snakes in captivity are over fed and if you feed mediums rats to a male this is definitely way more food than it needs so it is likely refusing to catch up.
BP can go of feed for various reason, hitting the "wall", seasonal, breeding, catching up etc.
If it persist make sure your husbandry is optimum and if it is wait it out.
Finally avoid bathing your snake it only adds unecessary stress and as we know stress can play a huge part in feedi bg refusal.