Panasonic KX-T2740 - Easa-phone Integrated Telephone Mini-Cassette Answering System Operating Instructions Manual page 65

Even if you forget to program the transler number to which the lcM is transferred,
the number can
be programmed from a remote phone.
I
Call your unit and press the Code Number during OGM.
l -
T
Press immediately after you hear the synthesized voice telling you the
number of recorded
messages.
the unit at home:
2
I For
3
lnitial Setting.
t r - E
Enter the phone number.
E T E
Final Setting.
5B