Hi, I'm Nathan.Sorry to hear that you're having trouble with this but I'll do my best to help you.
If you have multiple handsets (within the same system), does this happen with all of them?
That points to a bad battery in most cases, can you please take the battery out of one of the other handsets, and insert into the "bad" one, then put it on the base to charge and let me know if that message comes up again.
Were you able to test this?
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