Not receiving all notifications

I have noticed Paul's response to user Daniel, where he suggests to post here first that he does not receive all notifications of the groups that he subscribed to.

I have the same problem. In many instances, I see only 'some' responses to points that have been raised, without seeing all of them and even without seeing the original post. Obviously, because I do not know what I am missing, I cannot tell how much I am missing. But it seems to me that it affects 50 % or even more of all posts.

I don't know whether this is now a discussion or a question, so I have left it at the default.

Best regards,