I was booked on AA flight 133 at 3:30. Upon checking in using AA's automatic check in system, I was directed to the 4:30 flight. This flight was delayed, but I was issued a boarding pass and seat assignment. At boarding time, nearly 3 hours delayed, and 4 hours after I had first checked it, I was called to the desk by an agent named Happell. She took my boarding pass, threw it out, and refused to return it. I had been in first position for standby. As a result of her actions, I was not allowed to board the flight, even though I had purchased a ticket, checked in, and received a boarding pass and seat assignment, while other passengers, who arrived after I had, boarded. A full refund with any appropriate penalties for this action would be the only suitable remedy.