Girls have a problem. Daughter was accustomed to breastfeeding (due to…

Girls have a problem. Daughter was accustomed to breastfeeding (due to being in the NICU because they were in the resuscitation room) Previously there were problems with sleep. We were prescribed syrup and it seemed like sleep normalized. But if the daughter loses a breastfeed during sleep, she immediately starts crying or getting fussy. She doesn't need food, but rather cries that the nipple is out. Has anyone encountered this? How did they cope with it?