This message means that your website has reached one or more of its available resources limit which could be CPU, memory or RAM in that hosting account.
This can spring up due to badly coded plugins or themes installed in your WordPress website (in case you have a WordPress Website), you could uninstall the plugins, watch out if error persists, if it doesn't you can proceed to reinstalling the plugins one at a time to be able to fish out the bad one among them.
You can chat us up in our Livechat, our support team will be more than pleased to help you out or you could consider an upgrade to Standard VPS hosting package or you can check out other KVM Linux VPS hosting or Windows VPS Hosting.
