The batteries are behind the little cover on the front under the keyboard. Leave the register TURNED ON while you pop the cover open. There is a little hook on the cover. Use the hook to fish the battery holder out and replace the AA batteries. you must do it with machine on, or you will lose settings when you remove the batteries. Once removed, press the clear button and hopefully it will work again. If they were too low, it might have lost settings already. In that case, a reprogram is in order
Registerman, July 2021