Already answered in the Jelly section of the forum :
When you make a call, you always see on the left a red icon that looks like a phone, and on the RIGHT is an icon that looks like an orange "unlocked lock." Lightly press the ORANGE icon on the RIGHT....the one that looks like and "unlocked lock".....and the display will immediately change and display in the center THREE new icons....MUTE on the left, KEYPAD in the middle and SPEAKER on the right. Press the "KEYPAD" ICON in the center and your keypad will appear....!
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