Delta Cancellation Policy states that passengers can cancel their tickets through the official website or by calling the customer service helpline. Furthermore, The Airlines has strong and welcoming customer service representatives available 24 hours a day, seven days a week. You can contact them via a helpline number for everything from reservations to cancellations. Simply keep your ticket number and any other details that will be necessary before calling them.

https://airlinespolicy.com/cancellation-policy/delta-airlines-cancellation-policy/