Digital ocean deployment -node.js app (Runs on ip, but not on domain)

I am trying to deploy my node.js app on digitalocean. When i open it on ip like 107.170.16.24:3000 , it opens perfectly.

But, when i open it on domain like theconnect.io . I see

This site can’t be reached

www.theconnect.io took too long to respond.

Ii checked nameservers and those look ok. Can someone tell me where is the error? Even if i know the error source, I may rectify it. But, right now i am confused , where should i look for error.

when i connect my ubuntu terminal and run "nodemon" command. It runs perfectly and shows me text like

root@nodejs-512mb-nyc2-01:~/poppop2# nodemon
[nodemon] 1.11.0
[nodemon] to restart at any time, enter `rs`
[nodemon] watching: *.*
[nodemon] starting `node ./bin/www`
in dir routes / index
moving to 404
onListening now
Db Connected

So, it looks everything is running fine as far app is concerned. Can someone tell me why it doesnt open when i type domain name theconnect.io

via Ankur Sharma