No paid up letters and Refund!!!!!!

Hi , I have recently paid up my fnb accounts and personal loans all have been paid up I have now been told that I cannot get a paid up letter for my personal loan account as I first need to get refunded my payment as I paid more than what was required , this is pathetic service I need my paid up letter !!!!!! I have paid Fnb more than what was required This is more reason why I would not want to ever come back to Fnb !!!!! Please can I have what is due to me I sent through my bank statement for my refund !!!!!!!just do the right thing Fnb give me what is due to me and my paid up letters !!!!!!!!!!