These solutions will not work if the employee was the only admin on the tenant and MFA protected the account.
- Check the email alias of the former admin. If you have access to the inbox, such as through Google Workspace, request a password reset for the user and reset the password for the tenant account.
- Check for another admin on the tenant. This admin can remove the previous employee account and add a new admin. Auth0 recommends you have multiple admins on a tenant.