AT&T Z331 - Manual (Page 24)

Receiving Calls
When.a.voice.call.comes.in,.press.the.Send Key.or.the.OK Key.to.answer.the.call..
Tip:.If.you.have.connected.a.headset.to.the.phone,.you.can.press.the.button.on.
the.headset.to.answer.the.call.
Adjusting the Volume
During.a.call,.press.the Volume Keys.to.adjust.the.earpiece.or.speaker.volume.
Using Call History
From.idle.mode,.press.the.Send Key.to.check.the.All calls log.
18 Calls