I have call control on both my landline and mobile phone. I access call control features on either phone just by dialing *99 (star 99), then you'll get a voice prompt directing you how to turn it on, turn it off, etc. You can also access car control ...
Call control can be temporarily deactivated on your mobile device. Just dial *99 (that's star 99) and the voice prompt will lead you through the menu to turn off, turn back on, etc. The only other way I know of, is to turn it on and off in the Call ...
