Deploy a MERN Stack App tutorial -Azure

I followed the How to Use Azure Credits for MongoDB Atlas: Deploy a MERN Stack App tutorial. It works on my computer, but when I deploy to Azure I get an application error screen.

And in the error log I get:

So, I changed in package.json the “main”: “index.js” to server.mjs and it gets through. No error logged, but I don’t get access to the site. I get a blank page with “Cannot GET /”