Error while creating subdomain droplet for a Node.js app

Hi,

I’m currently creating a new droplet where a Node.js app will live on a subdomain. I setup the droplet using Ubuntu 18.04, installed Nginx and while configuring the subdomain in the “/etc/nginx/sites-available/sub.example.com” and received an error below when running the command “sudo nginx -t”:

nginx: [emerg] unknown directive “listen[::]:80” in /etc/nginx/sites-enabled/example.com:3 nginx: configuration file /etc/nginx/nginx.conf test failed

I’m not sure why I’m receiving this error, this is my first time building a droplet and am a front-end developer who knows very little about back-end processes.

Also, when I found a forum talking about this error, found and ran a command to list off all sites enables in nginx and this is what I have:

/etc/nginx/sites-enabled/sub.example.com:        listen 80;
/etc/nginx/sites-enabled/sub.example.com:        listen [::]:80;
/etc/nginx/sites-enabled/default:	listen 80 default_server;
/etc/nginx/sites-enabled/default:	listen [::]:80 default_server;
/etc/nginx/sites-enabled/default:	# listen 443 ssl default_server;
/etc/nginx/sites-enabled/default:	# listen [::]:443 ssl default_server;
/etc/nginx/sites-enabled/default:#	listen 80;
/etc/nginx/sites-enabled/default:#	listen [::]:80;
/etc/nginx/sites-enabled/example.com:	listen 80;
/etc/nginx/sites-enabled/example.com:	listen[::]:80;

Hope this helps, I’m 110% lost on what to do and how to proceed so any helpful tips and suggestions is greatly appreciated :) Thanks!