All I do is apologize
For a song I wrote in 2005

He is talking about You’re Beautiful, which was released May 30, 2005. Since it’s Blunt’s most famous song (along with Goodbye My Lover) and he’s one of the most criticised artists, most of that criticism is directed towards that song in particular.

Blunt is precisely aware of this too which makes for a brilliant twitter feed to follow.

A good example:
https://twitter.com/JamesBlunt/status/808599054989070336