I would highly recommend getting accurite thermometers (Walmart) as the ones you have are really not reliable. Also how are you monitoring the UTH?? It can and will spike to temps over 110 degrees. What substrate is that you are using?

I ask all this as sometimes it is a husbandry issue when they will not eat at that age.

Ask the person you bought it from what they were feeding....frozen thawed or live? That could be an issue as well.