I have just purchased an Astra Design 55 plate

I've been looking at the Astra manual and it tells me that I can select menu options on the information display by 'using the left-hand adjuster wheel on steering wheel: rotate and press adjuster'

I'm pressing this wheel and nothing is happening. I can't get past the information which shows radio channel selected. I'm trying to see the trip computer info etc etc

When I press the BC button I get 'No Function' on the display

Any ideas what i'm doing wrong? I'm hoping it's something basic rather than a fault