Stuck in Birmingham

[griffgray]

Had a great day up at the Classic Car Show last friday, however the sat nav seems to think I am still in Birmingham.

As I have only had the car a month or so I was wondering whether I am pushing the wrong buttons or has it jammed itself and is there a way to reset the system. I have removed the disc and inserted again. Wondering what to try and slightly concerned it might be expensive to fix.

Any thoughts would be much appreciated.