What are the temps in the snake's enclosure at (both cool and warm side)? Where's your humidity sitting at generally? Are you measuring with a decent digital thing or one of those analog jobbies? What sort of enclosure is it exactly? What type of lid does it have? What is your heating source? What's the room like that the enclosure is in as far as temps and humidity? What sort of substrate are you using? Is the enclosure located near a window, doorway or against an outside wall?
Sorry for all the questions but I know that sort of stuff is what folks will need to know to give you specific ideas for getting the snake's enclosure back in spec.
~~Jo~~