Hi there and welcome
Just to check, the base is showing a light that it has power correct?
Remove the batteries from the handset and the power to the base unit and wait 5 minutes.
connect the power to the base unit, wait 5 minutes, put the batteries in the handset, power it on and tell me if you can then register it with the base unit please.
It is the mainboard in the handset that has faulted. We have ruled out the other causes for this
I am really sorry about this and you are going to have to return the phone to have it 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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