The account shows 1 out of 2 sites is currently being used, however, you are only licensed for 1 site, therefore you may use the activation keys for the same site, one for http and one for https.
To change to a different site you must deactivate the current site from your account page here, then enter the key into the new site. Use this form to provide us with screenshots of any errors you receive, or provide us with login credentials if you want us to take a look at the installation.
We remain at your service.