Currently customers must reach out to the support team to check if email delivery to an Atlassian account has from blocked. Some common reasons include email bounces while the email address was deactivated by the customer's organisation, or the email address did not previously exist.

It would be nice if there is some indication within the organisation admin hub that shows if a managed account is in a state where they cannot be sent any emails from Atlassian.
And in addition, perhaps allow organisation admins to remove the blocker for email delivery for their managed accounts.

Notes

More information on this topic, here: Jira Cloud email notification suppression list and why users don't receive email notification

There are now two self-serve features for removing a user's email address from the suppression list in certain cases:

• For new users (who have not yet logged in for the first time) clicking the Resend invite link will remove the email from the suppression list.
• If the user has a verified account (i.e. they have logged into your Jira instance before) and the suppressed email notifications are being generated by a Jira Software or Jira Work Management project, project admins now have the ability to remove the email address from the suppression list using the Project email audit

If the self-serve options are not available to you we recommend creating a Support Ticket with us. For a quick resolution, please include the affected user's email address in your message.