********* and unprofessional deduction of fees for an insurance policy I never PURCHASED

nedbank has been deducting money from my account for an insurance policy i never purchased or even knew about. after much deliberation and confusion (five months of confusion at nedbank becuase nobody could tell me what this policy was for & why i needed it ,if my credit card is always paid up) nedbank admitted that they made a mistake. BUT they cant refund all my premiums because of prescription & offered 20% of what they stole from me. my understanding is that you must accept an insurance policy before premiums can be deducted. I hardly even used my credit card & its always paid on time so why would i need insurance. i had no idea that they were deducting premiums because they almost never issues statements on credits.i only noted the deductions this they upgraded the APP.how many other people out there pay for policies they never purchased, they don't need or even have knowledge about it?