With a message like this: 

"WARNING : We noticed some fraudulent activity with our theme OR couldn't connect to our servers for some reasons (check with your host that your server can connect to teslathemes.com). If you still can't fix it please contact us in 5 days to fix this or Zero framework page will be blocked."

The second thing after checking for an active account is suggesting to make sure that allow_url_fopen PHP directive is enabled

Note:  The themes that were being sold on "Ink Themes" and "Greedeals" over 3 years ago were producing this error.