The factory restart returns the clock to an “out-of-the box” default state which often resolves any issue.
1. Remove all power from the clock.
2. Press one of the buttons on the clock at least 20 times to clear all memory.
3. Verify that the clock is blank before proceeding (there may be lines painted on the screen that will show when there is no power).
4. Leave without power for 15 minutes (very important).
5. Power up the clock with fresh batteries.