hi, my baby is now almost completing 2 months. she is preterm and her weight was 1700 kg at birth time, and now she is 3 kg. But she is not taking breastfeed and cry a lot when taking breastfeed, so I have to express and then give it to her. And that Expressed milk is not sufficient for her so I need to give her formula milk maximum. So what should I do to give her Breastfeed and she can take easily?