itunes purchase

If the song is an Apple Music (subscribed) song, and you want to purchase it, click the three dots next to the song name (select song on a list to see the "dots"). Then select Show in iTunes Store. iTunes goes to the song's album page in iTunes Store, where you can buy it.

If you do this, please post back with the outcome. If the song is currently on a playlist (as an Apple Music song), is iTunes "smart" enough to replace it with your purchased song. In other words, does the purchased version of the song appear on the playlist (replacing the Apple Music version).