Apbco
Cancellation of insurance debit orde

I have cancelled my debit order with the insurance company on the 28 May 2013, the debit order was submitted to the bank from the insurance company on the 1 June 2013. As the debit order went through unpaid, Standard bank charged me an unpaid fee of R115.00 which they refuse to reverse. I personally think that there were enough time for the insurance company to have stopped the debit order and although they have submitted the debit order for payment also be liable for the unpaid fee of R115.00 what I must pay now. Being a single parent with dependants I think that R115.00 is worth more to me at this stage, and that I have cancelled the policy at the insurance company due to the fact that I cannot afford it anymore.
please assist in this regard