Try moving the clock to face a different direction. Also the reception varies a lot throughout the day (bad near sunset and sunrise); most radio clocks rely on

Try moving the clock to face a different direction. Also the reception varies a lot throughout the day (bad near sunset and sunrise); most radio clocks rely on gettings the occasional good reception and running in the conventional way the rest of the time. So it can be a case of waiting a day or two for the clock to get a good time reception.