Add Admin to a Membership

Hi Simple WP Membership
I don’t seem to be able to connect my WP admin user to a membership so as soon as I protect anything the plugin does not allow access. When I try to add the admin user to the membership I get this message:
This email address ([email protected]) belongs to an admin user. This email cannot be used to register a new account on this site for security reasons. Contact site admin.
For testing purpose, you can create another user account that is completely separate from the admin user account of this site.

Am I missing something? Do I have to create another account as admin to build the membership part of the site.