iTunes displays wrong artwork
I have an iPhone 6 with iOS 9.0.2 installed. In iTunes, when sorting by "Artist," the software displays an image for that artist. Sometimes it uses the cover art from one of the albums from that artist, and sometimes iTunes substitutes an image of the artist that must come from its own database, since it's not an album cover or anything that I have ever uploaded. A bit annoying that iTunes doesn't give me a choice, but I can deal with it. I have one artists that shares the same name as another band, and iTunes has automatically substituted an image for the other band. I cannot, for the life of me, figure out how to fix this. Is there any way to tell iTunes that it has selected the wrong image and to substitute the original album art instead?
Thanks for any suggestions.