Itunes won't let me pick songs
My iTunes hasn't allowed me to pick out individual songs for months now, the little check marks are completely gone. I recently got the iPhone 8 and thought that would help but it still only downloads 1 song (the same one all the time) or my entire library. I have the latest version of iTunes and have tried uninstalling and reinstalling it, but it simply hasn't worked. I'm not sure what to do at this point.
iPhone 8, iOS 11.4.1