We'd like to know more. Are your subs reporting that they're not receiving notifications or that your videos aren't showing up in their subs feed? Also, could you check if they are facing issues receiving desktop, mobile or email notifications (or all of the above)? Let us know.
Thanks for the info. Make sure you select 'Notify subscriber' under Advance Settings before you publish your videos. Also, could you please ask your subs to check their notification settings: https://goo.gl/T1T4kC . Hope this helps.