Williams is uncredited and didn't realize at first that he was the vocalist. He explained to Genius
"Kid Cudi initially did that hook and I just did harmonies and a supporting vocal for the melody. When Blueprint 3 came out, I looked at the track list and saw 'A Star is Born featuring J. Cole.' But I had no idea who J. Cole was, and when I listened to the song I heard a hook that I'd never heard before, because the last time I heard it, Cudi was singing the lead vocals and my voice was only supporting him. For two weeks, I listened to the record and thought, 'Wow, this J. Cole is really killing this hook.' But it's actually me!
What ended up happening was that they took Cudi totally out of the mix and pushed my vocals up to make it the lead. So it's my voice on the record, but for two weeks I was listening to myself and thinking it was some dude named J. Cole."