How long have you had him for? What are the specific's on his cage? What size enclosure? What substrate? What temps (high and low)? How many hides? How is it heated? Also, where did you get him from? A pet store or a breeder?
This information will help us be able to help you out much mroe, its hard to suggest something without knowing as much as possible about the "case".
A couple suggestions though:
If you have not had him for very long (less than a week) he might just be stressed out, try leaving him alone and keeping him out of the way of traffic he should eat.
If you have not had a fecal done you probably should. Parasites are a problem in reptiles and one of the first signs is not wanting to eat. Simple bring a under 24hr old fecal sample to your vet.
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