Impossible to cancel my contract!

I contacted Autopage via their website on 16th February about upgrading my phone. After a couple of days when I had received no response from them, I took out a new contract with another supplier.I then phoned Autopage to cancel my contract. I waited on the phone for 35 minutes with a voice saying they had a few problems, please be patient. Eventually I gave up and left a message on their website to cancel my contract. Still no response