Had a friend who managed to latch her baby again after stopping (due to medical reasons). She was sharing with us that what helped was paying attention to her baby's hunger cues and offering the breasts at any chance possible. However, be careful not to force the baby to drink if he/she resists. Will take some time, but hopefully, baby will be breastfeeding again soon.
Think it's a good sign that your baby has no problem latching despite not drinking much for now. You can try feeding when your baby is about to fall asleep as his/her drinking may be more instinctive.
Good luck!!