8 Week old BP will not eat

[Danster430]

hello all and Happy Thanksgiving.... i am need of advice on my now 8 week old BP. i got her 3 weeks ago and she refuses to eat at all.. i have done tons of research and narrowed it down to what could be one thing and i doubt that is it because i have 2 other BP that are 3 months and have different cages same heat, same lights, same exact cage set up and they eat within moments of dropping rat pups in the enclosure. NOW my little 8 week old i have no idea what is going on. i weighed her last week and she only weighed 54g, i had to assist feed her and she went to 70g and yesterday she dropped to 68g. i placed the fuzzies in her habitat and she just strolls on by them with no care or concern, they do not phase her at all, more like she thinks they are supposed to live in there to. i had tried day feeding, i tried night feeding, i tried a smaller container and covering it and she just acts like she has no interest at all. when i got her on a Monday the shop said she would be ready that Friday, but i waited to give her time to adjust and she absolutely has no interest. i am starting to wonder if she was even treated right at this shop she was at, i found articles after the fact on the owner and he was charged with not proper permits and not having them in healthy conditions and some of them had mites. if i did my research on the shop, i probably would not have got her there. so i checked my BP further and found she DID have a few mites on her only 5 or 6. so i immediately gave her a bath, bought mite spray, bought new container and all new items and she has not had any mite problem since. NONE of my other 2 had mites at all and have NOT had eating issues and they came from 2 different places. so i did research and see a item i could fix is her temp. all day her container sits at 80 degrees, she has a heating pad on the bottom of her container on her hot side and her hide sits on top of it. then she also has a cold side with a hide also. so i notice at night when i turn the day light off it drops to 70, i know that is NOT GOOD and i am fixing that and getting a red light, so for 12 hours she will have a day light and night she will have red light. i use coconut husk based substrate. and her enclosure 10 inch deep plastic tub. i have thermostat in there to watch the temps as well and fixing that problem now. she is not handled all the time, maybe no more than 15 minuets in the evening. she is not showing sides of shedding at all, she is to young to be sexually active, she is kept in her own cage and she is left alone for 48 hours after feeding.she does not show signs of stress, she does sleep all day, comes out at night, she does wander around. i am at a loss and now wondering if anyone else can give any other advice. i HAVE tried BOTH live and thawed and it makes no difference at all, she has absolutely no interest at all. i am getting the feeling that maybe she has never ever ate before i got her, i honestly do not know if she did or not. BUT by the charges the shop owner had makes me think differently. i leave the fuzzies in her container at the 1st offering about and hour, the second time about 30 minuets and the separate container another 30 minuets. she does drink her water, and will EAT when i have to assist feed her. My question is how can i get her caught on to learn to eat on her own?? anyone have an issue like this?? advice?? thoughts?? is it possible she has never ate since she was born?? i do know if she does not start on her own in the next 2 feedings i am going to take her to the vet. she does not look sick at all, just acts like she does not know how to eat if that make sense. sorry for the book, but more information the better. i just do not want to continue to put stress on her by assist feeding, but i do not want her to die either so i will help her all i can. thank you