CHICAGO (CBS) — This is the story of a flute fiasco. An out-of-town musician on Monday night was desperately hoping to find the professional-grade instrument he accidentally left on a Chicago Transit Authority Blue Line train.

He left it behind as he was scrambling to figure out where he was going in an unfamiliar city, and he told CBS 2’s Dana Kozlov it is irreplaceable – having been left to him by his grandmother.

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It was chaotic. Flautist Donald Rabin was rushing to get off the ‘L’ at the Logan Square Blue Line subway stop. He had his phone, which he needed to catch his Lyft, and he was also juggling bags.

And then he realized he had left his $22,000 flute on the train.

“So I sprint back down the stairs and my heart is racing,” Rain said.

Now, Rabin, 23, is trying desperately to find the flute. He left it wedged between the CTA Blue Line seat and a train wall Friday night.

Rabin has spent hours riding the Blue Line searching for the instrument himself ever since. He reported it lost to both the CTA and the Chicago Police too.

“I’m just really scared that somebody had, like, tried to sell it or whatever – and it means a lot to me,” he said.

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The Missouri native and current master’s degree student at the Berklee College of Music in Boston said it is not just the flute’s $22,000 value that has left him crushed. It’s the sentiment attached to it.

“It’s a professional flute that, when my grandmother died, this was part of the inheritance that I received, and so I like to take that little bit with me whenever I go play the flute,” Rabin said.

Rabin said Chicago Police are reviewing CTA security camera footage to see if they can pinpoint who walked off with the flute. Rabin never thought it possible he would ever leave it behind – intentionally or not.

“Everybody makes mistakes, and I feel like this was a great learning opportunity for the other musicians out there,” Rabin said.

Rabin returns to school at the conservatory on Tuesday. He’s hoping if someone found his flute, they will return it to the CTA lost and found or to Chicago Police.

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