In some scenarios, you may need to unregister an admin, and re-register them. To do this, follow the steps below.
Click the Search icon 🔎 and filter to Team members and Email address.
Input the admin's email address and click View profile on the relevant profile.
Click the action cog ⚙️, then click Unregister.
Head to the company, click Settings, then Admins.
Click +New admin
Enter the required data, then click Save invite.