Question - I don't get an indication of unread Forum posts

I have noticed that I do not get unread replies highlighted when I check the main page/ landing page of a topic, neither do I get an indication of unread replies when I open the assessment main page.

This is under my account as a tutor, which I seem to remember used to happen before unless I am confusing it with my account as a Student. 

When log in to the other unit as a student I can see that there are so many unread posts under the title of the reflection and when I open the page where all reflections are listed , I can see number of comments and number of unread replies ( which includes the original comment if I have not yet read it) 

My main concern is that I have missed a few comments and replies from students, which may have benefited from a reply or a comment by a tutor, or where some misunderstanding may have needed a correction or an update etc.