Being signed up for additional product that I didn't apply for!!!!!

Last year December app**** for a car finance with MFC Nedbank which I got approve and my installment of (2000)started this year January as per agreement and I have been getting calls from their agents trying to sell products which I refused, I eventually picked my phone and gave the agent some time trying not to be rude he signed me for product that I was not aware of and they have added additional 179 to my installment, since from February and I wasn't paying attention to this thinking maybe its addition cost that I had to pay, last week I decided to call and find out what 179 is for only to find out I have been signed up for cover that I am not aware of, I have the same cover that they claiming that I signed up for with them with old mutual and metropolitan ,why on earth will I open three same covers under this rescission, I called to cancel the stupid policy and request for a refund, and then the agent called me again and they told me that they will escalate my query, this morning they called me again and played the record to me and I didn't hear the part where I am sayin yes it's fine I will take the policy, the only time I said yes was when I was engaging with the agent as the sign that I am listening to what he is saying not that that I will take the damn cover, there is no way were I was asked about beneficiary as norm when you open such cover there must be someone who will be able to claim, I requested my refund and they telling me that it can not be processed, I am starting to regret choosing them to fund my car,MFC they rob people we got salary cuts, we going through recession and they adding cherry on top to make thing difficult for people they consider their client by taking their money, I AM NOT HAPPY AT ALL WITH THEIR SERVICE IS SO PATHETIC ,