No Push Text Message Notifications - Android

When someone texts me through my RingCentral number or I get a Voicemail, I don't get any push notifications on my Android phone (Galaxy S8+) until I open the Ring Central app. This means it might be hours or even days before I see that there's a message, missing important communication.

I've looked for notification settings within the app and in everything seems to be turned on. How do I fix this?