Unhelpful and ********* treatment of customer

A flexible and helpful consultant called my fiance' while in my company to sell medical insurance. It sounded like a needed and good product so we agreed to the terms and requested the first installment to be deducted on the 2nd October 2015. As we had started our own business around that time and unfortunately the funds that came in and out of our accounts were understandably not fixed, as a result we sent an email requesting that (we were still interested in the cover at that time) the deduction be delayed one more month. We also stated that a few personal details on the forms sent to us needed to be amended and requested a consultant call us to ensure they were done timeously. At the time of debit, my fiance' also called the call centre to confirm our email sent, as no call was received and was arrogantly told by a consultant that it was our choice regarding the date debited and it can only be changed in writing. We emailed again and told them in writing to cancel the policy but have only received harrassing sms's and repeated attempted debits, no phone calls and only emails and phone apps to continue with the policy, to state a few.