Typically, the seller will send you detailed instructions, which may include a free return shipping label Run 3 and a return address.
It seems there’s an issue with the product you received, and you’re looking to return it under warranty. For return or warranty inquiries, it’s best to reach out directly to customer support for guidance on how to proceed. While the link you provided is focused on queen ants and ant colonies, they should be able to help you with the specific return process for your DDR5 heat sinks.