Q: i have been charged £21.99 for i tunes match.....

iTunes Match isn't an app, it's a way of having all of your music stored in the cloud and available on your computers and devices : http://www.apple.com/uk/itunes/itunes-match/

If you haven't subscribed to it on your computer's iTunes then you can contact iTunes Support via this page : http://www.apple.com/support/itunes/contact/ - click on Contact iTunes Store Support on the right-hand side of the page, then Purchases, Billing & Redemption