Know how to call when i miss a payment

I've been dealing with my husbands credit card since being handed over to LGR Incorporated. On the 30th July 2015, i managed to settle the account and requested the Collections Agent who i dealt with (Cora Van Wyk) to confirm that the account is settled and closed after paying the settlement amount on the said date. I then received a statement that there is an amount of R70.14 due on the account after settling. i then sent an email to the address on the statement and to date i have received no feedback from Standard bank (email sent on the 8/8/2015). I am not willing to pay the R70.14 as i had requested closure of the account and received confirmation that it was done. i would like urgent feedback regarding this matter.