Insurance on account

I noticed on my monthly account that I am billed for insurance of R 36-36 each month. When I phoned into query I was told that I signed on my agreement that this would be added to my account. I said I didn't require insurance and was then told that I wouldn't be able to open the account if I didn't sign. So, I said I am forced to take out insurance which I don't require if I wanted to open the account. Is this legal and if not, what steps can I take to have the insurance removed from my account going further. I don't believe that I should be forced to do anything of the sort.