Unauthorised Contract Insurance Cover - Vodacom

I recently upgraded my cell phone contract via the Vodacom online portal and declined all offers of any insurance but I have since received an sms to say Vodacom has activated a "contract cover" insurance policy on my contract. Despite me calling Vodacom and being told to send an email to ********** and then sending them numerous emails, to date no one has been in touch with me to acknowledge my complaint nor have they done anything about cancelling the contract insurance cover which they initiated without my consent.