Ge Spacemaker I Have A GE Spacemaker Xl1800 And When I Select A Cooking Time It Shuts Off Before It's Done?

I have a GE spacemaker xl1800 and when I select a cooking time it shuts off before it's done? - ge spacemaker

Once you click Start for a few seconds and then stops, and the screen shows "care, such as eating - while cooking on the left. I do this several times before it really works. What is the problem and how can I solve this problem?