We will need to know more about your set up before we can really assess what the problem is. The reason ball pythons are such picky eaters is if their husbandry isnt correct then they will not eat.
What are your temps and humidity? How are you measuring them, like what sort of thermometer? How are you heating the enclosure? Are your heat sourcing being regulated by a thermostat? How many hides do you have and how much coverage does he have to hide in? A pic of you setup would help a lot (If you don't know how to upload pics the easiest way is by using the free app Tapatalk)
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