Hi @vpsinghbe –
This error generally means either that your server is overloaded and/or that your hosting provider is blocking access to the xmlrpc.php file that Jetpack Boost uses to communicate with your site.
To resolve this, please check with your hosting provider to check the load on the server. Additionally, if they are limiting connections to xmlrpc.php they will need to add our IPs to their allowlist as explained here:
https://jetpack.com/support/how-to-add-jetpack-ips-allowlist/
