I’m sorry to hear she pushed it back out, with a severe case of prolapse like your hen a vet probably need to get involved so they can stitch it up, you can try and keep pushing it in but I don’t really know how much that will help, rest will probably also help her hopefully Gain a little strength back. Right now your task is to keep her alive and make sure she drinks and poops. Chicken can go a couple of days without eating but drinking is really important. You could also add some vitamins, electrolytes or sugar to her water to give her a boost of energy

You’re doing a great job