Just to confirm, are your subscribers not receiving notifications or are they delayed? Also, mind sharing screenshots and more details from your subs, we'll take a look!
Your subs can double check their bell settings for the channel & make sure they've opted-in to receive all notifications & not just "occassional". After that, make sure their app & device settings are turned on: https://goo.gl/UCRcbp . Let us know if things still aren't working!