If you need to file a complaint against a merchant or defend your rights on the Alibaba platform, you can follow the steps below:

Log in to the Alibaba homepage and click the "Customer Service" button in the upper right corner;

In the pop-up drop-down menu, select the "Complaints and Suggestions" option;

On the new page, select the appropriate complaint type and fill in relevant information, such as order number, complaint content, supporting materials, etc.;

Submit the complaint and wait for Alibaba customer service to handle it.

If you cannot solve the problem through the above methods, you can also try to contact Alibaba's customer service hotline or customer service email for help.