Transcript Requirement
It seems that many Bee Gees documentaries on YouTube don't have transcripts.
For the !summarize command to work, a transcript is required.
If you can find a documentary with a transcript, I'll be happy to help summarize it for you.
Correct YouTube URL
Here is a correct YouTube URL for a Bee Gees documentary:
Please try this one, and I'll attempt to summarize it if possible.