Socket.io tests not passing

Hello guys,
I can’t pass the first socket.io test, no matter what I do. I believe my code is functional (I have tested it and it works), but the automation process with test doesn’t go over it successfully. I noticed some problems with previous tests about authentication and found out that many users had problems because of wrong boilerplate. But now I can’t get passed socket.io first challenge: link. Does anyone of you have similar problem?

My glitch project: link

User Agent is: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:72.0) Gecko/20100101 Firefox/72.0.

Challenge: Advanced Node and Express - Set up the Environment

Link to the challenge:
https://www.freecodecamp.org/learn/information-security-and-quality-assurance/advanced-node-and-express/set-up-the-environment

It looks like freecodecamp testing module had some problems connecting to my app. I added cors to my server.js file and now it works.