Because they are all house the same way does not mean the husbandry works for everybody the same, some are more difficult than other and a little tweaking is often necessary
You need to provide more info
When was it purchase?
How often you've been handling him?
Exact weight (same as the girls does not tell us anything)
Enclosure size?
Exact temps (how (type of thermometer) and where they are measured)
The more info the better.