There is a recall on this. Your dealer should replace the lock cylinder and key free of charge.
GM will notify owners, and dealers will inspect the vehicle to see if the key can be pulled out when the ignition is off. If it can, dealers will replace the ignition cylinder and keys, free of charge. The recall began in October 2014. Owners may contact Saturn customer service at 1-800-553-6000. GM’s number for this recall is 14506. Note: Until a vehicle has been remedied, owners and operators are advised that when exiting, to be sure that the vehicle is in "Park, " or in the case of a manual transmission, that the vehicle is in the “Reverse” position and the parking brake is engaged.