In Jira Service Management Automation, the "Edit Organizations Field" action offers the option to "Use reporter's email domain."

This feature extracts the domain name from the reporter's email address (e.g., "atlassian" from "example.com@atlassian.com").

However, there may be situations where including the top-level domain (".com" in this case) is desirable for the customer organization name (e.g., "atlassian.com") as the Customer Organization Name