For security reasons KKBOX cannot update your credit card information directly. You will need to cancel the current subscription and re-subscribe with a new or different credit card.

To cancel the current subscription:

Go to KKBOX Online Customer Service 

→ choose "Signing Up and Account" or "Payments and Accounts"

→ "Change of payment method" and submit the form.

Customer Service will notify you as soon as subscription has been cancelled.