I tried the solutions provided here link by Aphrim. But I'm not understanding how to fix this. I tried using different browsers and I tried going to this here (https://cdn-mathjax.codeforces.com/MathJax.js?config=TeX-AMS_HTML-full) .
This is how it's showing when I open the network tools in Chrome. This is how it's showing image
But, it's still not working. Please help me.
UPD: Now it's working again. I don't know how it suddenly started working again. I think it's a bug from cf backedn mathjax site. Because, many of my friends also faced this issue.
Thanks a lot for those who tried to help me.