Passengers can cancel a Delta Airlines flight within 24 hours of purchase, according to the airline's 24-hour cancellation policy. If the reservation was made a week or more before to the flight's scheduled departure date, the airline will issue a full delta refund policy of the ticket fee. If passengers cancel a flight a few hours before departure and the flight was booked less than a week in advance, the airlines will demand payment of a penalty that will be determined by the airline's fare rules.

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