My 3 monyh old daughter refusi to drink. She only drank 400 ml from morning 9 to 1 a.m. she only drinks her in sleep. Dont knw what to do?

Appetite. It is normal that a baby's appetite fluctuates, as much as ours do, at a given time. 400 ml = 13 oz in 16 hrs, so she has been drinking about 3.2 oz of formula every 4 hrs. which is not too bad in a particular day. If the lack of appetite continues, especially if she stops gaining or even loosing weight, that would be a reason for concern. I hope you are keeping your pediatrician informed.
Gaining weight ? please check if she is gaining weight on infant growth chart? your pediatrician may tell you if there is a problem. from 9 am till 1 am are 6 3 hourly feeds if she took 60-70 ml per feed, total will be 360-420 ml, which is the lower limit of normal, normal weight gain will mean that it is enough for her.