I was honestly stressed out last summer when my sister’s wedding date shifted and I had to cancel my Delta flight to Savannah. I thought I’d be stuck with a huge loss, but I found that the best way to or modify your plans without losing your mind is through the Fly Delta app. I just pulled up my itinerary under "My Trips," hit "Modify Flight," and then "Cancel." Since I had a Main Cabin ticket, they instantly issued me an eCredit for the full amount. It was way faster than sitting on hold!