Need some help with a Facebook Issue

For about a week I have been having this problem with Facebook notifications/comments, let me try and break it down for you:

let us say I go to website and read a blog post and want to comment on it, it uses the Facebook commenting system. When I do leave a comment I start getting notifications, these notifications and not about people commenting on my comment, these are notifications say "Jimmy Bob commented on the same article as you".

A broader breakdown:

What I get notifications about

1. People commenting on the same article

What I don't get notifications about:

1. People liking my comment

2. People replying to my comment

3. People commenting on the same comment that I replied to.

I have gone through all my settings and as far as I can see nothing has changed.