I tried all four of my Hong Kong credit cards and all declined. I called CC Company they said they approved the test charge of 1 dollar from Airbnb, yet did not receive any further instruction from Airbnb.
I then called Airbnb, and they send my a manual payment message, yet failed. They then said my account was temporarily locked due to too many failure and told me to try again one hour later....
I tried again the next day morning, yet still failed.
Finally, I changed currency to Chinese Yuan and tried Alipay. Suddenly everything went smoothly. All I need to do was scan the QR code using my Alipay App and approve the transaction. And then, woosh, DONE!
Thanks Alipay! Thanks Jack Ma!