Sorry this doesn't look like a WHMCS site

Hello!

I am trying to setup the WHMCS WP Integration plugin and I believe I have set the URL correctly, however, I am seeing this error:

Sorry this doesn’t look like a WHMCS site at [http://manage.mustardseedhosting.com/] Make sure your WHMCS Integration settings are pointing to the correct URL and that the WHMCS site is set for the Portal template in Setup | General.

If I go to Settings -> General under WHMCS, I only see Five and Six listed in the “Template” dropdown, no Portal listed.

Can you tell me what I’m doing wrong or what the issue could be?

Thanks!

Sri