In Bitdefender GravityZone I was able to normally block the sites I wanted, however youtube does not block it at all.
I blocked it by category, and even added it to the exceptions *.youtube.com as blocked, but it doesn't block!
Since you need help with business product, @Alex_Dr or @Andra_B (they both provide support for business products) could take a look here and help you with the issue.
Also, you can always contact the Bitdefender business support:
Have you tried issuing a new policy for a single endpoint in which to block Youtube? Can you also provide a screenshot with the current rules so we can double check if everything is in order?
Thanks for the help, now out of nowhere blocked lol.