Map Module doesn't erase previous map markers after moving photos

I am running LRC 15.3 on a MacBook Air. I’ve never experienced this until today. If I move a photo in the map module the original marker is left behind until I exit and restart LRC. It gets very cluttered very fast. If I change photo directories, the markers from the previous directory are also left behind until I exit LRC and restart. I have been using map module to geotag lot of older photos where I forgot to, or couldn’t, geotag as I went. I don’t think I’ve changed any settings and I installed 15.3 in April and have been using LRC constantly since then. Has anyone else experienced this and is there a fix?