Yogesh, I saw your ticket earlier. You're on an old VS3 package, not the new VPS-3 package. We sent out an email last Christmas about this free upgrade but you must have never replied. Open a ticket with sales and they'll gladly upgrade your account.
This particular plan upgrade will require a VPS reboot because of small virtualization system changes, but this only takes about 30 seconds in most cases.
https://support.knownhost.com Once we process it, it's near instant. Like I said, only a 30 second reboot is required.