I have and Amana "Big Oven" range. I used the self-cleaning today for the first time, and the door locked light flashed and then went off, indicating that it was finished and the door would unlock. There is now an F-9 error code on the panel. We cannot get the door to open. I have tried shutting off the breaker for several minutes and also tried unplugging the cord from the outlet. The door still will not open. Please help!