The purpose of this part is to ensure that carriers promptly refund consumers for: (1) fees for ancillary services related to air travel that consumers paid for but were not provided; (2) fees to transport checked bags that are lost or significantly delayed; and (3) airfare for a flight that is cancelled or had a significant change of flight itinerary where the consumer does not accept the change to the flight itinerary, alternative transportation, airline voucher or credit, or other compensation offered by the carrier.