settlement smart loan

I took out a smart loan with fnb which i was paying by debit order i missed one repayment and they took me over to thier attorneys NDS which then sent me an sms saying section 129 may be issued on your smart account if R400 is nt payed immediately that was dated 15/01/2016<br> I then on the same day called fnb for a settlement letter and it was sent to me and it dd say i have 10 days to settle my account i payed an amount of R2835.47 on the 20/01/2016 when i request a paid letter from both parties NDS tells me should sent them a proof of payment and Fnb is saying i owe im realy tired regarding this the call centre is not helpful at all please resolve this