When you make or receive a call on the TeleConsole you will be presented with the Active Calls/Call options screen.
If you switch to any other TeleConsole screen or another app you can return to this screen from the notification drawer (accessed by swiping down from the top of your device) and tapping the relevant notification for the call in progress.
If you don't see a call notification you have to ensure that notifications for the TeleConsole are enabled. See more information about this here.
