I would add as well that if dehydrated you should buy hornworms - they love them and are a really good source of fluids. Our BD got lethargic and didn’t want to eat or move around much and the vet did some bloodwork, which pointed toward dehydration. We also syringe fed pedialyte mixed with warm water - but you’d need to be careful not to do this without knowing for sure because too much liquid isn’t great and also please be very careful administering the fluids so the BD doesn’t aspirate any. You can look up videos on how to do it the right way (usually by searching how to give BD medication by mouth). Taking them outside is also great for getting them to perk up and also of course is the best source of UVB in direct sunlight. Good luck and thank you for caring enough to try to help the poor guy