Can you help me with logging in?

Hello,

I just purchased your directory plugin. When I try logging in I get this message:
"Your server had a problem connecting to WPMU DEV. Please try again.
If this problem continues, please contact your host and ask:
"Is php on my server properly configured to be able to contact https://premium.wpmudev.org/wdp-un.php with a GET HTTP request via fsockopen or CURL?"

I was just wondering if it could be because I am using the plugin on my subdomain.?! http://mombook.homeworkingmom.com