milk quantity —-2 percent of body weight per feed is adequate and feeding on demand as baby ages

If the baby is passing urine 6-7 times per day and sleeping calmy after feeds then feeding is adequate. I hope ur baby has crossed birthweight. As u have only mentioned current weight i dont know about weight gain. Feed ur baby as much he tolerates . Dont try to forcefeed.

Respected ma’am thank you for your query Your baby should be taking about 90 ml per feed 6 to 8 times a day. You can increase the feeds to 540 ml per day An easy way to know if your baby is getting enough milk is by knowing how many times he urinates in a day If he urinates more than 8 times a day then you know that he is adequately feeding

If u r giving 400 ml of formula milk then I wonder how much breast feeding u r giving. I would suggest u to shift to breastfeeding completely gradually. Check his weight on regular basis. Cues to well fed baby are if he is sleeping for 2-3 hrs after eac feed, passing urine 6-10 times in 24 hrs and gaining weight properly.