fsoz The reason the light is on is that there is a message not cleared.so if you clear the message it will go out,
If it is on the Operators phone it most likely is the general delivery mail box. Depending on your number scheme 98 or 998 or 9998,
Dial you voice mail, * ,your mail box number, your password, #, 1 and follow prompts.
If you have used default numbers and a three digit number scheme. 165 will be it. Alternative dial out then dial your voice mail number, # , 6 , * ,then box number & follow prompts. This is all in the Panasonic "Subscriber's Guide" page 2.2
Cheers