Just to confirm, have you tried setting up your device level notifications with these steps: https://goo.gl/K88coK ? Hope this helps.
@TeamYouTube
hey, so like. If y’all see that I sub to someone. Regardless of a stupid bell. LET. ME. KNOW. WHEN. THEY. UPLOAD. A. VIDEO. PLEASE. Hence the frickin SUBSCRIBE button. Just thought I’d let ya know before I come and take all y’all jobs. 
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Thanks. Twitter will use this to make your timeline better. UndoUndo
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