Unknown or duplicate parameter: NodeCommand

I used Procfile to deploy app

in Procfile

web: npm run deploy

In package.json, added new command deploy

 "scripts": {
    "deploy": "npm run build && npm run start"
  },

I just encountered this very same issue. Upon investigation I found that "NodeCommand" is the legacy way to run your application with custom commands.

https://docs.aws.amazon.com/elasticbeanstalk/latest/dg/create_deploy_nodejs.container.html

I removed the ".ebextensions" directory and added a file called "Procfile" to my source directory.

Inside Procfile, try putting the following:

web: npm start

Make sure you update your repository with these changes if necessary before trying to deploy.

Hope this helps!