Hi there and welcome
It appears you have set the register to program mode. Turn the key back to Z/PGM, then press SUBTOTAL (you might have to press it twice).It may print a list. This is normal. Then turn back to reg mode, and it should now function
Let me know the results please
Remove the power to the register, wait 10 minutes, then connect the power and tell me what then happens please
It is the internal memory that has faulted.
A corrupted firmware can cause this. But we have ruled this out by trying to hard restart it.
I am really sorry about this and you are going to have to return the register to have this replaced. It will be covered by the warranty if this has not expired, and the replacement will be done at no cost to you.
I am really sorry about this, and if you have problems, or would like any additional information or assistance, please do not hesitate to let me know.
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