I Was Charged Monthly by Cerebrum IQ After One IQ Test

Cerebrum IQ, I made a one-off payment for an IQ test and later discovered that I had been signed up for a subscription service costing £9.99 a month, without any clear indication that this would happen. I have no idea what this charge is for and I never agreed to continue with any ongoing service. I do not want this subscription and have no use for it. Please cancel this contract immediately and stop charging me. Sue B***, cageen****@hotmail.co.uk