Due to the bank card organization, different currencies will be used when swiping the card due to different clearing organizations. If it is a UnionPay merchant, the RMB account in the card will be debited, and if it is VISA, the US dollar account will be debited. If the foreign currency account overdraft reaches the upper limit, you cannot use the U.S. dollar account. At this time, you can call 95588 customer service, transfer to the credit card account of manual service, and request repayment of RMB foreign exchange purchase. Use the money in the RMB account to purchase U.S. dollars and then repay the foreign currency debt. After the repayment is completed, the foreign currency quota is released, so that you can continue to spend foreign currencies.