Getting out of contracts can be tricky. I had a problem with vodafone just before xmas which was a bit of a nightmare to sort, so I started going down the route of contacting the ombudsman.
Before you can contact the ombudsman you have to get a letter of deadlock, so I had to send a registered letter of complaint to their head office.. but in the end it actually got sorted before I had to go that far. It took about 2.5 months though before they came up with something acceptable. This
is the procedure I followed for vodafone - presumably there will be something similar on your own providers website.