Panasonic KX-TG2560S is 'Out Of Range'.
My phone kept saying it was out of range even though the headset was right next to the base unit.
Also, the Caller ID stopped working. Funny how you can get used to something like Caller ID even though a lot of calls say 'Out Of Area'.
Hmm, maybe there's some karma to these messages. A bad karma.
So I found this Panasonc website and looked up the phone.
After following the tips on the page, my phone now works and I have no problems.
Good job Panasonic! Nice helpful website you have there.