calling my Node.js API application which is deployed on a 22.04 Ubuntu droplet with Postman doesn't work

Hello,

I have thoroughly followed all of the steps and prerequisite tutorials in this link for my 22.04 Ubuntu droplet setup : https://www.digitalocean.com/community/tutorials/how-to-set-up-a-node-js-application-for-production-on-ubuntu-22-04

All of the steps seemed to be set correctly, I’ve checked nginx, ufw statuses, etc. Correctly set the localhost port to the port of my node.js app.

But when I try to test one of my application’s endpoint with postman - it doesn’t work. When I call just the https://mydomain.com, it returns the HTML of “Welcome to nginx!” page that I can see when I open the domain with the browser. And when I try to call https://mydomain.com/endpoint , it returns 404 error message.

Seems that somewhere the request is not being redirected/put through correctly. How would I go about debugging/fixing this?

Thank you.