Hi , My Baby Has Not Gained Enough Weight Since

Hi ,
My baby has not gained enough weight since her birth .I am top feeding her with breast milk. I tried different formula lactogen , nan pro and now she is on similac advance. I would like to know which is the best formula milk , so that she gains good weight along with overall development .I have heard about enfamil also.

She also gets constipated formula milk and since last 1 month or more she is very fussy about bottle feeding . She takes only 300 ml of milk per day but for 3 months it's suggested that baby takes 180 ml 5 times so that makes it to 900 ml. So I am bit worried with her growth.

Thanks