The Beatles released a hit called “Don’t Let Me Down” near the end of their time together. Subsequently, a 2010s group created a song with the same title that was more successful. The group recruited a popular singer to perform vocals on the song.
In the 1997 book Paul McCartney: Many Years From Now, Paul discussed the origin of “Don’t Let Me Down.” “I think it was a genuine cry for help,” said. “It was a good song. We recorded it in the basement of Apple for Let It Be and later did it up on the roof for the film. We went through it quite a lot for this one.”
Paul discussed his role in recording the track. “I sang harmony on it, which makes me wonder if I helped with a couple of words, but I don’t think so,” he said.” It was John’s song.”
Source: cheatsheet.com