Firebellies are usually voracious eaters. But their prey items must be active and moving or the toads wont go after them that is why they prefer crickets. I feed mine in the daytime when I can see them eat. What is the temperature? Sometimes they don't eat if theyre too cold. Also try feeding them in their original enclosure sometimes if you move them to a different place to feed them they're more interested in escaping than eating.