Block customers from purchasing your products
To block problematic customers from purchasing your products, go to the Mass-block emails section in your Advanced Settings. Enter one or more email addresses, separated by a new line, and click the Update settings button.
NOTE: Adding SampleEmail@gmail.com will also block SampleEmailfirstname.lastname@example.org and Sample.Email@gmail.com. This will only block customers from your Gumroad, and they will only know about it if they try to purchase from you again in the future.
Revoke a customer’s access to their content
If you’ve noticed a customer distributing your content illegally or otherwise violating your terms, you can revoke access to their content.
Go to the Customers dashboard, find the desired customer, and click the Revoke access button.