That's odd, does it shows 'Subscribe' on the channel page? Also, could you check your 'Subscriptions' and let us know if those channels are missing? Share more details and we'll take a look.
@TeamYouTube Eh, it feels like I've been unsubscribed from a few channels I've used to watch.... Even tho i never clicked the unsubscribe button 
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Thanks. Twitter will use this to make your timeline better. UndoUndo
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