Could either be the memory battery or the keyboard has shifted between [F0] and [F1]. Start with the initial reset then enter the Clerk code in. Otherwise do the keyboard shift/reset. If neither of these help, the memory battery will have to be replaced
Cashtronics
October 2020
Did you solve it? Sounds like a bad battery if it doesn't accept your PIN number
Registerman
September 2020
Automatic Answer
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