By Elizabeth Hur

PHILADELPHIA (CBS) — Mistakes happen – but it’s far from comforting when they happen at the airport and when they concern security.

So imagine one man’s surprise when he tried to check in and the airline tells him, he checked in earlier and he was already in the air.

Brad Gertz says it happened to him on a trip he makes every other week: from Chicago to Philly and back.

Gertz said, “I can tell you, I lost all color in my face, I was nervous and furious. I would say at least five times, they’re telling me, I’m not me.”

This time around, he was at Philly International on Sunday, trying to check in for his flight at 1 p.m. with American Airlines when he’s told, he got on an earlier flight.

Gertz recalled, “A 10 o’clock flight that left a few minutes early at 9:53.”

So how is that possible? According to American Airlines, it was a mistake. A spokesperson explained in a statement:

“A boarding pass with Mr. Gertz’s name on it was inadvertently given to another passenger yesterday when they arrived at PHL to check in for their flight. One of our employees realized the error after it happened and gave the other passenger the correct boarding pass. Because of this mistake, it appeared that Mr. Gertz was already checked in for and set to take an earlier flight. Mr. Gertz’s itinerary was not updated to reflect the mistake until he arrived at the airport later that morning to check in for his originally scheduled flight. We have spoken to Mr. Gertz to apologize for the confusion and offer him a travel voucher as a gesture of goodwill.”

Gertz responded, “So they say, ‘It was our fault, we did give someone your boarding pass so we let them through.’ This person, whoever this was, that got through under my identity that easy and made it to the gate? Who says anyone else can’t?”

Joe Schwieterm, an aviation expert added, “Multiple failures had to occur for this passenger to get through with the wrong ID and when you let people through when not matching names, the whole essence of the system fails.”

Fortunately, Gertz did make it home eventually but he says he won’t be flying American again anytime soon.

Gertz said, “No one likes to throw around the word ‘bomb’ or anything but God forbid, this guy did something stupid, my name my identity is attached.. And their answer was here, have a $300 flight and let’s forget all about this. The ironic part it it was a $600 flight anyways.”

Late Monday, TSA also responded to our requests for answers. Press Secretary Ross Feinstein said, “TSA is reviewing allegations that document verification procedures were not followed properly at Philadelphia International Airport. Passengers are subject to a robust security system that employs multiple layers, including watch list matching, thorough screening at the checkpoint, Federal Air Marshals, armed pilots and a vigilant public, as well as many others, both seen and unseen. The system is designed so if one layer of security does not meet our standards, there are many others in place to ensure the safety of the traveling public.”

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