This is not easy to find unless he is willing to provide you with relevant information. When applying for a credit card, you need to submit your personal email address. The bank sends a credit card bill every month. If you can see this email, you can see the bill. Or you can also receive the monthly bill in the bank's WeChat public service number, but you may need the relevant verification process to view the details. In addition, call the bank customer service hotline, and the customer service will inform you after verifying the relevant information.