Kindly be assured you can update your card information via the [Sakura Mobile My Page].
Sakura Mobile My Page: https://myaccount.sakuramobile.jp/auth/login
If it's your first time to log in to the [Sakura Mobile My Page], kindly refer to this article on How to log in to [Sakura Mobile My Page] for the first time?
1. After you log in to your Page, kindly click on the three dots on the upper right as shown in the below picture
2. From the menu, please select the option (Account):
3. To change and update the registered card, kindly click on the pen mark as shown below:
4. From the next page, you can choose the option (Update Card Information).
5. Please fill in all the required information and submit the request.
We accept VISA, Master, JCB, AMEX, Discover, or Diners.
We do NOT accept direct bank transfers, cash cards, or prepaid debit/credit cards.
If you face any issues when updating the new Credit/Debit Card, please take a screenshot and send us an email to firstname.lastname@example.org