World-renowned cellist Lynn Harrell says Delta Air Lines has banned him from it's frequent flyer program.

The reason for the ban: Harrell would collect miles whenever he paid for an extra seat for his cello, which he says is to delicate and valuable to fly as checked baggage.

15 years ago, a travel agent set up a separate Delta SkyMiles account for Harrell's instrument under the name "Cello Harrell." Harrell collected frequent flier miles for both himself and his instrument ever since.

In January, the air lines put a kibosh on the musician's accounts through a letter. On Monday, Harrell shared the letter on his blog.