ABSA unauthorized repetitive debit orders

Yesterday I received a call from a telesales company calling on behalf of ABSA. They were offering life and accidental cover and I declined the offer. Today I wake up to a debit order of the same policy they were offering with the reference NAEDO TRACKED DEBIT ORDER, ONECALL / OC150919SO634. When I try to reverse the debit order, I then realize, there was another debit order of the same amount two days prior in my account. This happened before they even called me. In 3 days they have debited me twice for something I clearly rejected telephonically. I cannot seem to reverse the two payments either.