Brazzers — unauthorised billing

My name is Edward Duddigan and I signed up for the trial membership. I decided before the period was over that I didn't want to fully join, therefore I cancelled the membership. However I have still been billed the £31.85. The terms stated I could cancel before the 7 days were up and not be charged from there after. Please look in to this, and I would like a full refund since the service has not been used after the 7 day trial.
Thanks.