Unauthorised payment deduction

Regrettably I also made use of this company today. Spoke to an online agent and was told to payR15.00 to have my question answered by an legal person. Next thing they deducted an additional R781.00 off my account. Now they claim I signed a subscription with them, which I never did. I did not authorise them to take off the additional amount. Requested the conversation btw myself and agent, but all they can say is that I signed a subscription.I made them cxl this subscription with immediate effect, but they refuse to refund me. Shocking business practices!