Eskom did not pay back money due to me

On December 18 my husband passed away, He had an eskom account ***). Shortly after his death I received a phone call that his account is in arrears and I requested a friend of mine to transfer the amount of R10 000 into the said eskom account, as I have moved to China and am no longer in South Africa. On April 24 Medaco Revenue Solutions informed me that the account has been handed over to them for collections. On May 21 an email from Rinae Raliwedza *** informed me: “Kindly note that your Eskom account has a credit balance of R-9,362.16 which resulted from your final bill when you closed this account. In order for the amount to be refunded, kindly send a letter confirming your banking details from the bank.” I informed her that my husband passed away and she requested documents of which I have send her like death certificate, ID’s, etc. On July 18, however, another email was received from Fortunate Nxumalo *** who said: “According to our reports you have a credit on your stopped account, kindly send us confirmed banking details with a stamp from the bank for us to refund .” Once again I informed him of my husband’s passing as well as my previous correspondence and on his request adhere to every request he had from ID’s, death notice, bank statement, marriage certificate etc. On July 25 I even send him my friend’s bank statement where it indicates the payment made with the account number clearly on the statement. Up to date, I have bent backwards to accommodate eskom’s demands to identify myself, proof that my husband passed away, given them the bank statement to proof the payment was done and still I received NOTHING back. Why did Medaco then called me and even send a mail that the account has been handed over if this was not true? Why did eskom request all these documents of me if they did not plan to pay me back the money which I have battled to get through into their account? Could you please help me to get answers from eskom as well as action to finalise the situation?