Unable to install any packages using yum

I am not able to use yum, with Errno 14] HTTPS Error 404 - Not Found
Trying other mirror.
To address this issue please refer to the below knowledge base article

https://access.redhat.com/articles/1320623

I checked this article, but it didn't work, also checked on google!
Anyone faced like this message before?
i am using Red hat 7

Thanks