Hello & Welcome,
I'm Greg and will do my best to assist you today.
Sorry to hear of any issue you are having with your phones.
Unfortunately, these are two different "generations" of Panasonic systems, which can not be linked together to transfer phonebook information from one to the other.
As a matter of fact, there are very few "consumer level" phone systems that have this capability at all. This "feature" is typically only available in some "business phone systems" - that have the capability to store hundreds and hundreds of phone numbers, and of course those phone systems are VERY expensive.
So the only way to move the phone numbers is to copy them from the old system to the new one - manually - by typing them in.
Sorry to have to give you this information, but I will only give you an honest and correct answer. Please don't hold that against me.
Please let me know if you have any more questions.
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Thanks, ***** *****