Zanussi Double Oven ZOD35802XK we have had if just over a year. The clock/timer aleays worked and we generally use the smaller oven. We turned the electric off and since we turned it back on we have no clock now and the main oven and the clock comes on if the top oven is on but if you turn the top oven off then the clock and the main oven doesn't work. Any ideas why?