she is completing 3 month but her weight is only 4 kg with formula feed... how I gain her weight

A. Namaste Mom CHeck with the weight gain progress and also the quantity of the feed being given per feed which is expected in the range of 100 to 125 ml per feed for 5 to 6 times a day monthly gain is expected in the range of 400 gm to 1 kg and by the age of 4 to 6 months they double their birth weight