I recently changed a business class booking Sydney/Cairns (same day different time) and paid a nominal change fee all looked fine. A minute later I'm advised by Visa that the card used had been replaced and so the transaction was declined. Corrected the card detail on Qantas but nothing more. In frustration wrote via Feedback pointing out system failing and asking that they either call me or point out how I can pay online. Today get a threatening email demanding that I call a 1800 number within 24 hours or the flight will be cancelled. The number had the usual 2 hour wait message but I waited for an hour as I had time but gave up. Is there not some way to make this payment other than spending hours waiting so i can give them money?