we were't able to verify the private key

I just googled that string, and it appears to be coming from a Captcha plugin. Do you have captcha installed on your site? Is it the default Joomla captcha, or a 3rd party extension?

In general, JFBConnect shouldn't be triggering the captcha response, and we do some testing to make sure we don't. Something sounds different on your site, and we'd need to know what that is.

I'd also recommend trying to disable captcha and test that way just to verify that it is indeed the problem.

Thanks,
Alex

Glad to hear we helped narrow things down. If you run into anything else, just let us know.

Thanks,
Alex