No experience with refunds. But I do have the experience customer service is horrible to reach, with anything being a bit complex like re-routing and the like costing countless times of calling, apping and so on. The website, app or chat usually cannot help, their Saudi number reroutes to what I think is a call centre that cannot help, in the end I had success with the local France office (I lived temporarily in France at the time) but only at the 3rd try. I was initially downgraded J -> Y but when I noted they again had a plane with J in the end they rebooked me to original fare class. My guess your best bet is hang up, call again until with a local office until you talk to a live agent willing to put you on your original flight.