Discovery Health - ridiculous deduction error

After a long negotiation with Discovery Health to transfer the medical aid from my deceased fathers estate to my mothers name, we have got this done. Thank you for that. No thanks however for the R19,196.00 erroneously deducted form my bank account. Nor for insisting that my 84 year old mother authorise the reversal - it is not her bank account, it is not her paying the premiums, nor was it het that made the mistake. You promised to call her two weeks ago to rectify the mistake - you have not. I think it is rude and inconsiderate to ask an 84 year old that is concerned about online ***** to authorise a transaction she knows nothing about. In what world is that reasonable? Can you please correct your own system error/ Can you please refund the money taken out of my account. Can you please do so now.