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) WHEN did this issue first begin?
2) How many TOTAL cordless handsets do you have with this system?
3) What phone service provider (phone company) you have for this phone line?
4) If you have ANY other devices (phones, fax, etc.) that are NOT part if the Panasonic system - attached to this same phone line and if so, are they working properly?
Please REPLY using the box below and the SEND button.