I want to change my credit card payment method for pixiv Premium – pixiv Help Center

If you'd like to delete a credit card registered as a payment method for pixiv Premium
You can check the credit card info and delete it here.
* If your pixiv Premium membership is processing for renewal, or you have an overdue payment, you will not be able to delete your credit card information.
If you'd like to change or update a credit card registered as a payment method for pixiv Premium
Depending on the plan you subscribed to, the procedures for revising your credit card information are as follows:

If you've subscribed to 1-month plan:
Go to your Premium Membership Subscription page > "Update" under the payment method category > Enter new card information > “Change” > and your change is complete

If you've subscribed to the 3-month, 6-month, or 12-month plans:
Go to your Premium Membership Subscription page > "Update" under the payment method category > Add a new card information or select the card you want to use > “Use the selected card” > and your change is complete

* If you change the credit card currently associated as your Premium Membership payment method, you will be billed using the new information when it's time to renew your membership.