We only accepted Visa, MasterCard, and American Express credit cards before. This time, JCB, Diners Club and Discover credit cards are new additions to the available credit cards. Followings are the same so far. The amount of money fluctuates depending on the status of the exchange rate at the time. When the payment is refunded, an exchange gain or loss is caused by a change in the exchange rate. We kindly ask for your understanding.