"Is secure" variable not working

[marketingalliance]

I'm using your plugin, and I can't get the {if secure}{/if} option to work.

On this page:
https://msmainstreet.com/test2
http://msmainstreet.com/test2

It doesn't matter what address you use, it still returns as insecure even though there is a security certificate in place. Is there a script or a function that is present with your plugin that my host may be blocking?

The code is very basic.
Is this site secure?<br /> {if secure}yes{/if} {if not_secure}no{/if}

I've tried the other variables in your plugin, and they're all working fine. Just not this one that I need.