We cannot @mention one of our new employees in Confluence Cloud.
He is setup like all others in GSuite, Confluence, and Jira, but his name won't appear in the user list when we try to @mention him in Confluence. It does work in Jira, though.
I don't know if it matters, but his email address was used by a previous employee in years past.
What can we do to get his name to show up?