Hmm, that's odd. It's possible that some of them might have changed their personalized settings for notifications – you can try this troubleshooter and see how it goes: https://yt.be/help/gti9 . Also if you can, ask for some screenshots from your subscribers and send them our way.
@TeamYouTube Can you explain to me why my people have no notification of my videos, even those who have the bell activated?
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Thanks. Twitter will use this to make your timeline better. UndoUndo
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