This is an FYI, as I seemed to cleared the trouble.
I recently got a new Android phone (GS-10plus) and noticed the Ring notifications were not working on the phone (despite the App setting being enabled for notification for my Video Doorbell Pro). Within the Ring App I disabled and then re-enabled the notifications for the Video Doorbell Pro, which immeidately generated an Android notification that nofitications for this App have been disabled. Enabling notification for the Ring App appears to have fixed the issue.
As a side note, I never installed the Ring app on the new GS-10plus but rather lI used the Android’s Backup and Restore feature. I am guessing there is some glitch in this process that resulting in the phone having notifications disabled for the Ring App.
Again, merely an FYI.