Notifs possible bug and clarification needed

I am not receiving all comment notifications. I came across comments on previous posts , just by chance, that I never received a notification for.

Also, is within the app the only place to get notifications other than in the Notification Center on iPhone?

I don’t get a badge alert or a sound alert. Wasn’t sure if these two options were just not implemented or are mine just not working?

IPhone XR
iOS 14
Beta user
Minor bug