Panasonic KX-TGM420 Operating Instructions Manual page 143

[ ]: "Playback"  [SELECT]
*3 You can also erase as follows:
[PAUSE]  [
"Yes"  [SELECT]
Calling back (Caller ID subscribers only)
1 Press [PAUSE] during playback.
2 [ ]: "Call back"  [SELECT]
Editing the number before calling back
1 Press [PAUSE] during playback.
2 [ ]: "Edit & Call"  [SELECT]
3 Press [EDIT] repeatedly until the phone number is
shown in the desired format (page 132). 
[TALK]
Erasing all messages
1 [MENU] [#] [3] [2] [5]
2 [ ]: "Yes"  [SELECT]  [OFF]
]: "Erase"  [SELECT]  [ ]:
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