Ultimate Facebook Login not working

I have installed UF and created the app in Facebook, entered all the API keys and secret codes and followed the set up process.

When I try to login using FB nothing happens. It does ask me for me FB login details and once entered and submitted it tries to work then just sits on the the WP login page.

In the admin area at the top of the UF admin area I get this message;

Warning: curl_exec() has been disabled for security reasons in /home/wwwtownchat/public_html/wp-content/plugins/wpmu-dev-facebook/lib/external/base_facebook.php on line 982

There is also an Error Log option under the Facebook plugin, it shows the same error repeatedly which is as follows;

WDFBModel::get_user_api_token exception Token not found

I am not sure what I have done wrong or set up wrong but if you can advise how I can fix this and get this plugin working that would be apprecaited.

Thanks,

Frank