1. Log in to official website, the e-commerce platform of Datang, and enter the personal center page.
2. On the personal center page, find the relevant options, such as "My Order" or "My Registration", and then click Enter.
3. Find the order or registration information you want to cancel, and click "Cancel Order" or "Cancel Registration" and other related buttons.
4. According to the system prompt, fill in the relevant information and confirm to cancel the operation.