Requested for cancellation and was told I'm still liable for subscription fees

I chose the Dimension 2 option for an amount of R1800 per month upon the Broker's advice. I specifically told him that I do not want to be restricted to Network doctors or hospitals. He assured me that I will be able to see any Doctor of my choice on this plan only to find out after my application went through that there are restrictions as to which doctors I can see. I have requested that my application be cancelled with immediate effect. Now I am being told that my subscription fee of R1800 will still be debited on 31 January 2018. I have read the terms and conditions and nowhere does it stipulate that I will be liable for the subscription fee if I decided to cancel my application within the first month. I think that this is unfair, ********* and totally unacceptable that I be charged a premium for a service which I am unable to use and is unsatisfactory to my requirements.