I found the answer. Press the button with the talking face. When it beeps just say erase phone book. It will ask " do you want to erase phone book? I say yes. It says "Phone book erased? All gone.

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"What you hear in a great jazz band is the sound of democracy. “The jazz band works best when participation is shaped by intelligent communication.”
Harmony happens whenever different parts get to form a whole by means of congruity, concord, symetry, consistency, conformity, correspondence, agreement, accord, unity, consonance…….