Digestive issues are hard on birds. They can recover, if it doesn't become too complicated, but it can be scary. It's important that they keep eating and drinking.
They can't digest milk, so it can make droppings look weird if the yogurt is milk-based. This can sometimes hide improvement. Probiotic powder sprinkled on her food, or a tiny bit in her beak, (maybe as a wet paste so she doesn't inhale it,) can be helpful.
Sometimes I try unsweetened applesauce for pectin, or meal worms or bsfl for protein. Sometimes their needs and interest in foods change, so it's good to have a variety on hand.