It's probably just due to the winter months if the snake was previously eating, but it should have started up again by now.

What are your temps? Make sure he has a good hot spot to warm up.

Leave the snake alone unless it's absolutely necessary to mess with it, so no handling and try not to "hang out" anywhere near it's cage.

try offering a f/t prey item a little smaller than what he snake would normally eat. just leave it in the cage over night near the entrance to the snake's hide. if that doesnt work, wait 4-5 days and try again but with a brained prey item.
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