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 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 and START with KX-TG, followed by a 4-digit number.
2) How many TOTAL cordless handsets do you have with this system, and if more than one, do ALL handsets have this same issue?
3) What phone service provider (phone company) you have for this phone line?
4) 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?
Please REPLY using the box below and the SEND button.
Sorry for any delay - I got cut off for a bit.
Can you check the MAIN BASE UNIT of the system, and see if you can find a model number printed there.
The format should be KX-TGxxxx - where xxxx is a 4-digit number.
NOTE that there is NO "A" - as that is for the cordless handsets only.
Also, what is the AGE of the system, and have the batteries in the system handsets EVER been replaced (with new batteries)?
Once more thing: When you say "landlines are working", what does that mean?