I would like to ask if your baby eats fruit or not. If not but eats congee, do add fruit. My son eats half banana (not more) on alternative days, good have soft stool daily. Drink some water/ juice/ soup in-between meals. Let baby move more so also more intestinal motion to let stool going out.
Really, i tried different formula milk brands before but not much improvement. Even when my son drinks breastmilk only, he passes stool once every few days.