Mazda 3 warranty

Ten days after our 2009 Mazda 3 ran out of warranty on the 21st of October 2012 we took it back to the dealer as it was hard to take the auto transmission shift lever out of park to select reverse. The gear lever kept locking into park. Mazda fixed the problem stating that it was a poor electrical connection. I asked if they would consider this under warranty, but the service manager flatly refused my request and they refused to let us take the car until the bill was paid. I thought that a bit of give and take on this was warranted, and I thought it was a harsh call by the service manager. He would not budge on the issue. Where can we go to complain?