Why can’t JS detect a var from .env (dotenv)?

Problem:

The server cannot detect process.env.PORT from my .env file, saying PORT=5000, and I have dotenv installed. process.env.port returns undefined Is something wrong?

I have a very basic express server that runs fine:

const express = require('express');
const path = require('path');
const dotenv = require('dotenv')

const app = express();
const port = process.env.PORT || 8080;

// sendFile will go here
app.get('/', function(req, res) {
  res.sendFile(path.join(__dirname, '/index.html'));
});

app.listen(port);
console.log('Server started at http://localhost:' + port);
console.log(process.env.PORT) 

On server start:

Server started at http://localhost:8080
process.env.PORT = undefined

console.log(process.env.PORT) on the bottom of express script returned undefined

I have dotenv installed, proof:

$ npm ls dotenv       
eloquent-javascript@ /Users/dana/code/eloquent-javascript
└── [email protected]

My .env file has the following content:

PORT=5000

What is wrong with my setup?

I have express.js, .env and installed dotenv via npm.

Question: Why couldn’t express.js grab my variable via process.env.PORT from the .env file?