My iPhone 6 is showing the incorrect artist name.

For some artist on my phone, it displays incorrect information about the artist. For example, in the Frank Sinatra songs, it displays the artist as Frank Sinatra, Dean Martin, and Sammy Davis Jr. even if the other two are not in the song. I have one song which is all three of them and seems like the information from that song has been transferred to all of the others. However, when I organize my music under Artists it still says 'Frank Sinatra,' it's only when I'm actually playing the song it says all three (underneath the song name.) I have tried resetting my phone and deleting the song with all of them from my phone and my purchased list but nothing has worked so far. Does anyone know how to fix this?