I need help editing metadata on foobar2000?

I have been editing the tags such as artist and genre but recently Some files refuse to cooperate with me. In genre I want to add multiple genres and for the most part it works but on this album set it refuses to separate the genres. Example "file 1" needs the genres "Rock" and "Pop". The instructions say to separate with a semicolon like this "Rock;Pop". Here's the problem It's been working with other files so the method isn't flawed but instead of finding "file 1" in both the Rock and Pop genres, it is found in the Rock;Pop genre. It is affecting the full album. I'm clueless.If it helps I'm using the newest version.