This would imply that the commenters are on private accounts that you can't see. I agree that it could be clearer when this is happening
someone on a non-private account replied to the comment of a private account. I got the notification, and the number went up, but the comment was not visible.
Probably I shouldn't get a notification for this reply either, then?
I recieved a notification for a comment on the post both times, neither i or the author have blocked the other, or on priv accounts but the comment is not visible despite the comment counter showing it
here's a post showing this issue - https://cohost.org/pervertsexposed/post/1263544-hey-fellow-yiffsters