Hi, I literally canceled a flight 2 hours ago with (so far) no problem to get cash refund. He offered me the voucher, but I just said I prefer cash and he was like "ok, no problem". Should be charged-back to my CC within 2 weeks. I called the US hotline: +1 18002479297.

Hope that helps!

*Hotline was for free but it took me 20min waiting to get through