The average hatchling is 55/70 grams so either your BP was a very small runt in the 30/40 grams or it is younger and was not started or barely.
Do you have any record (hatching, feeding)?
The problem is with an animal that size and obviously not well established is that it might be very hard for you to get him to eat.
My guess it was a small CH that might have a meal maybe two and that was it, not the best thing to get started in this hobby which is why it is so important to get an established animal from a good breeder.