Delta Refundable Ticket Policy

Delta Airlines offers non-restricted refundable prices that can be refunded up to three hours before the planned departure.
It is acceptable to cancel refundable main cabin tickets on Delta up to two hours prior to the planned departure.
Any refundable fare combined with hotels, vehicle rentals, or any combination of the three offers a refund on the flight fare only, according to Delta Airlines' cancellation policy. The third-party vendor can be contacted for hotel and auto rental refunds, which are not covered by the Delta refundable cancellation policy(https://cutt.ly/EKZ4uls).
Passengers may request a refund on a refundable Delta ticket in the event of a no-show, but they must pay a no-show penalty of $150 USD and a Delta cancellation fee of $200 USD before receiving the remaining fare value.

Check also : https://cutt.ly/WKZ4wB6