As a merchant, you may be processing orders that are coming from other marketplaces, such as Amazon or Ebay. And you may want to prevent these customers from being eligible to enter in your loyalty program. You can achieve this by simply blocking any email coming from a particular domain from becoming a program member. This guide explains how to set this feature.
Create an email domain blacklist
To add the email domains you wish to blacklist, go to Display -> Email Notifications -> Edit Email Settings.
Scroll down to the bottom of the page to the Email Domain Blacklist feature and add the domains:
Save your changes once you’re done.