Secure Pages not populating

Hi,
I just installed the plugin and I am trying to just secure one page through the New Page sidebar. I am getting an error in Chrome that says “This webpage is not available”

You can see the page here: https://windycityyouthbuild.org/full-application/

When I have enable “Force SSL Exclusively” in the HTTPS Admin Panel the whole web site has the same error. So I took that off and just used the sidebar option within https://windycityyouthbuild.org/full-application/. Now the web site is available but the page does not show and shows the “This webpage is not available” error.

Please advise.

Thank you very much!
Pablo

https://ww.wp.xz.cn/plugins/wordpress-https/