Bank Failing to close an account an charging fees for services NOT rendered

I sent the bank an instruction on the 19th of May 2019 to close my FNB transactional account nr ***. The bank subsequently did not follow the instruction and since then I have been charged monthly account fees on an account that is not in use. I have sent a number of mails requesting the crediting of the account fees and closure of the account but nothing has happend. Last year I received SARS refund and it was in error paid to the FNB account. After a extensive fight FNB transfer the funds over to my Discovery account. After the payment was done, I received s SMS stating that my FNB account is now over drawn and this is due to the fees that FNB has levied each month. I have not being using the account for almost three years and no transactions was done on the account after my first instruction. I have also not received any statements on the account since the I requested the closure. I get no response to may mails and FNB call Center is useless. FNB need to issue me with a letter confirming that the account has been closed or I will take it to the Banking Ombudsman and Social media. This is your last chance.