A Delta Platinum Medallion passenger asked the airline’s generative-AI booking assistant, Delta Concierge, to cancel only the outbound leg of a round-trip award ticket. The assistant confirmed the return flight would remain booked, but Delta’s backend processed a full cancellation of both segments and refunded the miles and taxes. When the passenger tried to rebook, she was quoted nearly double the original cost, and Delta customer service reportedly declined to restore the original reservation. Delta later attributed the error to a bug affecting partial-trip cancellation requests, which Concierge does not support.