Sorry to hear they're not doing well.
Wingless fruitflies will crawl upwards, but little chams over a day old normally start eating them up very quickly, so few flies should be escaping. Encourage the fruitflies to stick around by keeping a piece of banana or similar on the bottom of the enclosure andor stuck on a twig mid-way height. Perhaps put only a half dozen in at any time, so the hatchling can easily single one fly out at a time. But in my experience I could dump 50 in an enclosure with 6 hachlings and all the flies dissapeared into bellies quickly.
I've heard sometimes a few fail to thrive, but I've not heard about a whole batch passing from not eating. I wonder if something about the set-up of their enclosures is off? Have you had hatchlings before? Do you know anyone in your area who has been successful in breedingraising hatchlings that could check it for you?
The day temperature should allow a range, from around 75 to around 85 (a little less hot in the hotest basking spot than for adults). Ensure there is a UVB source. Keep the humidity fairly high, water three or four times a day (but not directly on the hatchlings). Make sure the enclosure is in a quiet, lowno traffic area where the chams wont feel threatened. If you're watching them, stay at a distance and keep still. Keep adult chams and other pets out of sight.
If in the end none eat and all die, you may want to take one to a vet for a post-mortum to find out if something was physically wrong with them? Dont know if they can open up a baby but they could xray for internal deforms.
But I hope it doesnt come to that, and that they get eating and growing happy soon!!!
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Sandra
BC Canada