I was having this same issue using replit… my problem was the public url that I was using to verify my solution…
The correct one should be something like this:
https://boilerplate-npm.<your_replit_acocunt>.repl.co
I know this is an old thread but just as an FYI to the original poster. Or anyone reading the thread that tries to use Netlify.
With Netlify it would have had to use serverless functions, not just the plain NodeJS code you get from the starter boilerplate. Not even sure what would be required to make it work on Netlify but it likely wouldn’t be worth the trouble.
You can use something like Heroku instead, or just use the Replit starter.