7 months drinks less milk

My 7 months baby is on FM and she drinks less milk now. It started when she has 3 meals a day and now she drinks only 90ml every 3 hrs instead of usual 150/180ml. At times when she didnt eat her dinner well, i thought she would drink more but still 80/90 ml only and she goes to bed to sleep throughout the night. Will she be ok? Is this normal? How do i get her to drink more?