Jetpack xml_rpc-32700

I am trying to connect my site with jetpack but it shows this error?

Your Jetpack has a glitch. Something went wrong that’s never supposed to happen. Guess you’re just lucky: xml_rpc-32700
Try connecting again.
Error Details: The Jetpack server could not communicate with your site's XML-RPC URL. Please check to make sure http://ksweb.altervista.org/blog/xmlrpc.php is working properly. It should show 'XML‑RPC server accepts POST requests only.' on a line by itself when viewed in a browser and should not have any blank links or extra output anywhere.

If you follow that link you will see a <script> section in the response. Maybe some plugin is injecting that code.