This likely won't be news for most of you, but for those who recently got their animals and are having a hard time getting them to eat: try feeding them with no lights on. This has worked 100% of the time for me (I'm assuming here that you've got all the basic husbandry setup dialed in: I've two hides, hot spot @ 88-90F, ambient temps at around 75-80F, humidity hovers around 60-65%). If you don't have the basics down then this might not be relevant at all - make sure the animal feels secure and has a warm spot to digest his meal after it eats.
I've a picky male Enchi who will only eat if I turn off all the lights (I use a headlamp with the red light setting on, which doesn't seem to bother him - I'm not sure if snakes can see all colors in the spectrum?). If any other source of light is on, he'll track the food (f/t) but won't strike. Leaving the food in the tub won't work either, even in the dark. If he really doesn't want to eat, then I just feed my Banana instead, who's a garbage disposal :-)
That is all, have a good day.