I have tried to send invite emails to 2 users under vigilant-ops.com domain. But they do not receive the email.
@Manish Jadhav Welcome to the Atlassian Community. What products were you trying to invite these users to?
@Andy Gladstone Confluence and Jira
Is this issue still persisting?
Have your users checked their Spam folders? If you are on Office365 Microsoft has tightened some of their controls and some emails that were previously not going to quarantine stuck there. You may want to check that.
Confluence and Jira