ABSA refused to assist on my request from the call centre

Here is what happened, Due to technical error of my card machine, my staff double charged one of my customer, i need to contact her or the bank can contact her for refund.firstly i need to identify which bank does this card number belongs to,because that's the only information that i have. i phoned around, Capitec, Standard bank,FNB, finally FNB consultant told me that was a Absa bank card number, so i called absa for assistance. the lady who answered my call was very arrogant, she keep on telling me that it's not allowed to check client details, then i said i don't need your client's contact details, shall we please have a 3 party call or could you please contact the owner to come for a refund, she refused to help. i feel that ABSA really need to look into their employee's attitude to their service commitment, and take it serious.