Shifting everyone to new server isn't a good idea usually so we tried a lot and all possible things to sort out the issue first. Usually this problem was coming in every 2-3 days but this time the server was up for 12 days before it went down unexpectedly.
And like I updated in last mail, that I am giving last chance to that server and if it went down again, I'll order a new one.
I ordered a new server which should arrive in 24-48 hours. In the meanwhile this server will be up for 3 days, kindly make the necessary backup yourselves.