For 3 months to 6 months, it should atleast be 180ml to 200ml with interval of 4 to 6 hrs gap. However, this depends on your child body weight and how much intake can she/he take in without having any vomiting, issues, etc.
Well then if this is the case, you can consult doctor for further advice. Sometimes, infants dont take much due to their feeding pattern change, constipation, etc. Also not all milk formula products will have the same suggested milk powder instructions. What I have encounter each check up during immunisation or doctor assessment their main questions will be milk intake. If certainly they mentioned this is not a cause of concern, then it is fine.
Young mummy of two beautiful girls Loves to travel, ✈