40 gallons breeder is for a full grown adult not a hatchling especially not a ball python and if your snake is not eating or not a voracious feeder at that age that means it’s telling you something. Your animal just went from a cozy and very secure environment in the form or a 6 quarts or v18 tub to a very stressful environment
You are gonna have to do make changes if you want to use a glass tank get a 10 gallons max, even than it may or may not work and if it does not here is what you can do New owner with non feeding hatchling, troubleshooting 101