Can NOT run rails application on my server's IP address only runs at localhost:3000

I deployed my rails application on the server with capistrano, nginx and puma, following this tutorial- https://www.digitalocean.com/community/tutorials/deploying-a-rails-app-on-ubuntu-14-04-with-capistrano-nginx-and-puma.

App is running fine in localhost:3000. I can also run on-> rails server --binding=My_IP I can see my app in action on-> http://My_IP:3000

When I browse http://My_IP , I saw welcome to nginx screen. But according to document, when I run - sudo rm /etc/nginx/sites-enabled/default sudo ln -nfs “/home/username/apps/appname/current/config/nginx.conf” “/etc/nginx/sites-enabled/appname” (Ofcourse I changed username and appname)

I can NOT connect to my server’s IP address (says Unable to connect… can’t establish a connection).

Nginx server is running. I also tried running with systemctl start nginx command.

May be something wrong with Puma? I can NOT connect my Puma web server to the Nginx reverse proxy? I am not sure.

I searched online, some people have puma.rb file but I don’t have(document does not mention). I just have Puma gem in my Gemfile. Do I need config/puma.rb file?

I have- Rails -v 4.2.5 Ruby -v 2.3.0

So my problem is I can NOT run my application on my servers IP address. App is only running default on localhost:3000 Is it problem with port 80? Puma is not connected to port 80?

I need help running my application in production.

Thank you.