Hello, girls, my daughter may not eat for 5-7 hours, but when I give h…

Hello, girls, my daughter may not eat for 5-7 hours, but when I give her every three hours she doesn't take any formula at all. I don't know what to do anymore? I told the pediatrician, and she says that she doesn't want it, so that's it. But four days ago she was eating constantly and didn't spit up with tantrums like now ? and now I don't know what to think about it. I feel like a bad mother and constantly think maybe this is because I left work for eight hours and left her with my husband's parents. Maybe they gave her something wrong and they're silent, saying everything is as I said, doing everything and