Oh, I didn't know about the bot. So I guess that's Piped (https://github.com/TeamPiped/Piped) which is a frontend like invidious (https://github.com/iv-org/invidious) and usually when it doesn't work switching instance should do the job.
Newpipe is a different project: https://newpipe.net/
On desktop you can also use FreeTube: https://freetubeapp.io/
That works for lemmy but it doesn't seem to be available on kbin yet.