Comments.

I do not know what is going on with the comments. I am not getting comment notifications anymore and I've noticed that some comments are showing up for me but they aren't being published, but nor is Google asking me to approve them. I don't get it. 

I also noticed that there were several comments that people left which were marked as spam for no reason and were never published. Some of these go back a couple of years, so I can only apologise if you left a comment and it never appeared on the blog.