Panasonic KX-TGD312BX Operating Manual page 45

Select "Greeting Only" in step 2 on
"Caller's recording time", page 44.
Note:
R When you select "Greeting Only":
– If you do not record your own message,
the unit will play the pre-recorded
greeting-only message asking callers to
call again later.
– If you use your own message, record the
greeting-only message asking callers to
call again later (page 39).
Answering System
45