I've rather given up. I needed to add a middle name to a passenger in my redemption group (a legacy of HK's covid response) even though, like many, I find it impossible to use any upgrade vouchers, certainly from business. It was impossible to make changes online. No sense from the phone number which used to be helpful but seems clueless now. In the end I gave up, cancelled my next Cathay booking and booked my next (usually monthly) London flight on BA, something I've not done before but am glad I did. I saved HK$16,000 and had an arrivals lounge at Heathrow, which Cathay no longer provides. I used to be a big supporter, certainly of the Cathay of the past but it's become quite frustrating dealing with them and having renewed my BA gold card I'm not sure I need a Cathay diamond card as well.