I don't display mine as a conversation but I did have a couple PM's from a couple different people received before I finally was able to read them. I will go through them and click them all, though, and see if that fixes the problem.
Post Merge: January 11, 2017, 04:23:08 AM
Good news, hathorcat! Your suggestion worked! When I clicked on a message about 10 or 11 down the page, the  in my alerts disappeared! Even though it had shown that it was opened and read, apparently somehow the system didn't think it had been.