Hi there, This may be due to regurgitation of milk during sleep. Nurse the baby with head end raised & let the baby sleep on her Rt lateral position ( turned on Rt side) During feeding chocking can be due to too much milk is flowing in the baby's mouth, Squeeze off a little milk before feeding if you are having too much secretions.
Next Steps
If problem persists, need a full evaluation to rule out Gastro-esophageal reflux. (GER)