Telephone inquiry, WeChat inquiry.

According to the query on Xicai.com:

1. Call the customer service number of the card-issuing bank and follow the voice prompts to check the billing date of the card. You can also transfer to manual service and contact customer service. personnel to inquire.

2. Follow the official WeChat public account of the card-issuing bank on WeChat, then enter the official account and find the "Check Account Button" in the menu bar to query the credit card statement date.