Why can I hear the programme sound but no video. Just the list of apps and the settings icon are displayed

I am trying to run a recent television programme on ITV Player. I have set up the right connections (I Think) and run the programme on my I Pad. I can hear the sound of the programme on the TV, but I cannot see the video. The television screen displays the list of available apps and the settings ICON. What have I not set up correctly.

Thanks