My 2y8m doesn’t poo in the potty

My 2y 8m old toddler has been pee trained first and I’ve been trying to poo train her which isn’t going well. I read the 3day potty training book and it did help us a lot but I’m a bit lost as she is refusing to poo in the potty. I filled her stomach with food and water she has been peeing but no poo. I’m about to give up and put on the diaper to make her poo. As of now she’s in her training pants. Any tips/advice?