There used to be a time where all of my reviews were counted on the list of available reviews for a product. While this hasn't affected each one of my reviews, if I'm looking at the page for certain reviews, there may be one other review (or more) that is also on the list of reviews for the product. What you'll see instead of the product featuring a star count for both reviews and a description that reads "2 consumer reviews"... instead you'll see "1 consumer review".

Is this a bug? What needs to be done to have this corrected?

It is a bug. I know it's been reported in the past (by me, and, probably, countless others). Don't know why it still happens. Perhaps this is something we just have to live with on the current system. (Hopefully it won't be a problem on the new system).