Is it free in Delta to change flights? You can change your Flight on Delta Airlines.com or the Delta Airlines app in four steps: Go to My Trips. Select “Change Flight” Select “Edit” to update your Flight. Or call Delta Airlines cancellation officials at ????+????-????????????-4????2((2????91)) (OTA). You can rebook to a different Flight at no charge within 5 days from your scheduled departure. Can I change an existing flight? Can you reschedule a Flight? Yes, you can reschedule or cancel a Flight by dialing +1-866-452-2691. However, you may need to pay a change or cancellation fee depending on the airline you booked with and the fare class of your ticket.