Delta told me my sons ticket was refundable and now they say it’s not.

I am writing for my son who is **. I booked this ticket and called to cancel it when I called I specifically asked if there was any penalization for the cancellation and they said no. I asked how it would be refunded they said ti would be a credit under the ticket number. I asked this question several times before I canceled the ticket. When I tried to use the credit It said funds unavailable. Today I called the ********** number and I had the most disturbing conversation with a man who said his name was John. He was laughing and rude the entire conversation and asked why I should think I should get money back if I canceled the flight? When I told him It was suggested to me that I call by a friend who writes a travel website and writes for the wall street journal and new york times he was ruder than before. I asked him his name and he said, John. and I said can I get your id number or last name he said I am sorry we aren't allowed to give out that information???? Really I said I would have to believe there is more than one John at Delta and he said I am John from Salt lake city and he and his coworkers proceeed to laugh hysterically as he told me this. I then said I am asking again for your last name and he said fine if you must its Solacd when I told him I was going to be taping the rest of the call he abruptly hung up. I have never been treated so rudely. We have been flying jetblue for years and just recently decided after reading reviews of Deltas service that we would like as a family of * to switch over to Delta and to get a Delta credit card but after today I am questioning that. I have now lost a travel voucher of $*** and an hours of work time dealing with Delta. To put it mildly, I am not happy. I understand companies are outsourcing their work to other countries now but to have to deal with this for your customers is beyond frustrating. Their is often a language difference which I believe is why I lost out on $*** and to be treated the way I was today would put off any consumer.