I have just bought a Quattroporte Cento and can't figure out how to get the car telephone to work. When I insert activated SIM card in the slot belowdisplay on the dashboard and press "telephone", the message comes up "telephone not available". At the bottom corner of the display it says "TEL OFF". There's nothing in the instructions explaining how to turn the phone on. I tried to look for this funcrtion in the car setup, but no success. Anyone knows? Thank you.