This exact thing happened at my school on their GM, the key has a series of pins it pushes on, to even it out to allow the key to turn, one of them are probaly stuck to not allow the key to turn... time for a new lock cylinder

Former owner of a 1995 Ford Contour GL w/ 2.0L ATX Proud owner of a 2005 Ford Taurus SE 3.0L V6 Vulcan --Looking for Commodore stuff (Drives, Units, Amiga, games, etc)If anyone has any of this laying around and wants it gone, lemme know --