How to fix the error cannot find dns server?

Question

Domain Name System

I posted a video in index.html and writes an error cannot find dns server. I'm building a project through open-server, maybe this is the problem? This is the first time I've come across this. I did not find a solution on other sites. Can anyone tell me what is the reason? Thanks in advance.
Here is the error from console: GET https://www.youtube%20%20%20%20%20%20%20%20%20%20%... net::ERR_NAME_NOT_RESOLVED
here is an iframe from html : width="560 "height="315" src=" https://www.youtube.com/embed/4Aa9GwWaRv0 " frameborder="0" allowfullscreen

Answer 1

I understood everything, this is my cant, it's all about phpstorm line translations.
I formatted the code incorrectly, that's why the error popped up, now I'll know.

Answer 2

The URL of the video is incorrect, obviously.