The method of querying China Merchants Bank credit card debt information through SMS is as follows:

1. Open the China Merchants Bank app on the mobile phone desktop.

2. After opening the China Merchants Bank app, click on the arrow in the upper left corner of the page.

3. Next, click Login pointed by the arrow.

4. After logging in, click Credit Card.

5. After entering the credit card page, click Message Service Customization.

6. On the page that appears subsequently, click to turn on the SMS service notification to check the amount owed through SMS.