This isn't a programming issue but a content license issue from YouTube. That message is telling you that the video contains copyrighted content, used without permission of the copyright owners. Those entities have exercised their right of ownership to control where their property is being used, and they have blocked it from playback on mobile devices and apps. The only way around this error is to find videos that do not use unauthorized (read that as illegal) content. As far as i am aware the decision to let the video play on external sites belongs to the video account holder under the Syndication section.
here's what the video says when you try to view it
"There are age restrictions for this video. It cannot be viewed in the built-in player. More detailed…
View on YouTube"