In most of the cases when a BP is fasting there is a reason behind it, often it is husbandry related, in that case make sure that your temperatures are 80-84 on the cool side, 90-94 on the warm side, of course this mean you need to have an accurate reading provided by a digital thermometer.

Check your humidity and make sure it is between 50%-60%

Make sure the enclosure is in a low traffic area.

Make sure your hides (2) are tight enough so your BP can snug in, all sides must be touching your BP's body.

If you handle your BP often, try to limit handling (Too much handling can cause stress)

BP will also fast to catch up and I can tell you that if you feed 2 medium rats a week I am not surprise to hear that your BP refuses to eat. This is way more food than your BP needs.

Because a BP can eat large amount of food does not mean he needs to.

If you want your BP to resume feeding and eat with consistency I would recommend you to downsize a bit.

BP can thrive with nothing more than a small rat (4 weeks old - 45/65 grams a week).

I never fed a medium rat, not even to my biggest adults.

The largest prey I feed is a small rat weekly and I never had any BP going of feed.