Hi all mummies, my baby currently is 2 months old with 80% Breastmilk and 20% Formula (S26). Is it normal for him to poo every 2-3 days? or is the formula milk too heaty?

I think that is because of the formula milk...before,my baby also poop every 2-3 days and his usually constipated. Sometimes,he’s crying while pooping. When I started exclusive breastfeeding,he poops everyday and he is not constipated at all.