We'd like to help. Just to confirm, do you see the notifications turned off on other devices and for other channels too? Also, could you check with your subs if they're not receiving notifications for your video uploads? Let us know.
Hmm, it could be possible that you may be signed into multiple devices with the same account and hence the issue. If that's the case, please sign out from all: https://goo.gl/84MFdo and see if that makes a difference.