title: NestJS address already in use :::3000
body: <p>I'm trying to deploy my NestJs server on a C-Panel hosting. The node_modules are installed properly same as every other file of the project. Everytime I'm trying to run the server it keeps sending me this error: 
  <code>address already in use :::3000</code></p>
  
  <p>this is my main.ts file:</p>
  
  <pre><code>import { NestFactory } from '@nestjs/core';
  import { AppModule } from './app.module';
  import * as config from 'config';
  
  async function bootstrap() {
    const serverConfig = config.get('server');
    const app = await NestFactory.create(AppModule);
    const port = process.env.PORT || 3000;
  
    app.enableCors();
  
    await app.listen(port);
  }
  bootstrap();
  </code></pre>
  
  <p>As you can see the server port is listening to the environment variable named <strong>PORT</strong> which I'm creating at the C-Panel and if it's not exist it listens to port 3000.</p>
  
  <p>Iv'e looking for three days now for solutions and didn't find one...
  Can someone explain to me what causes this error and how to avoid it?</p>
  
  <p>Maybe there is a way of making the server inject a port to the node app?</p>