Your TV box needs to be connected to a TV aerial and BT Hub in order to watch Freeview TV channels, subscription channels, and On Demand programmes.
Your Freeview channels come through the TV aerial, and your subscription channels and On Demand come through your broadband.
Make sure that you have a working aerial connected to your box at all times. You'll need an outside aerial that can receive a digital Freeview signal. A small indoor aerial is unlikely to be good enough, even with a booster.