Hello & Welcome to Just Answer,
I'm Greg and will do my best to assist you today.
Sorry to hear of any issue you are having with your phones.
To help you with this issue, may I ask:
1) The FULL Make (brand) and Model Number of the phone system you are working with? If this is a cordless system, that model should be printed on a sticker on the bottom or back of the MAIN base.
2) If you have ANY other devices (phones, fax, etc.) attached to this same phone line and if so, are they working properly?
OK - very good.
May I also ask:
1) How many TOTAL cordless handsets do you have with this system, and if more than one, do ALL handset have an issue, or just one?
2) If you have ANY other phones (not part of the Panasonic system) attached to this same phone line and if so, are they working properly?