Multiple problems

It seems like something on your site is blocking automated checks. Our server tries to imitate a browser, but some firewalls or anti-spam software can still detect that it's a 'bot' and not real traffic. When your server sees this type of traffic, it returns a 503 error.

You can see similar 503 errors from other automated tools:
httpstatus.io/
www.urlitor.com/

Other tools do seem to make it past the filter though and return a proper 200 code:
www.webfx.com/tools/http-status-tool
tools.seobook.com/server-header-checker/

Unfortunately, there's not much we can do on our end to get around this type of block on your site, but I hope that helps explain. Obviously, I'd recommend testing multiple ways to make sure you're not incorrectly blocking 'good' bots, like google, bing, other crawlers and, of course, real people.

I hope that helps explain,
Alex

I just sent the IP address by email. Let me know if you run into issues after whitelisting.

Thanks!
Alex

Thanks for the tip on the link for VK. We've fixed the redirect so the product page should show properly. With JFBConnect v9, we broke out many providers into their own plugins to simplify subscription management and development. In case you didn't see our full announcement blog post, I'd recommend looking through JFBConnect v9 Released! for more details.

As for the Fetch Network Settings link not working, can you tell us if you're seeing an error message or if there are any other details you can provide on what's not working?

Thanks,
Alex