According to information on the official website of the Patent Query website, you can file a complaint again after an Amazon patent expires. The complaint steps are as follows:

1. Log in to the Amazon Seller Center and open the "Intellectual Property Protection" page.

2. Click "Submit Infringement Complaint" and fill in the relevant information, including links to infringing products, brand registration certificates and other evidence materials.

3. After submission, Amazon will review the complaint and may require additional supporting materials.

4. If the complaint is approved, Amazon will take measures, such as deleting links to infringing products, suspending seller accounts, etc. It should be noted that filing false complaints will have adverse effects and may lead to legal liability .