Paid Up Letter

We have settled an March 2016 with Telkom after the account was closed. Up to now no one at Telkom has done there job and now my wife is sitting with a bad credit record and we cannot get a home loan approved since her credit record still shows that she owes Telkom money. We got the invoices from Telkom directly showing Telkom owes her R9.44. We are about to loose the house we want to buy because we cannot get a paid up letter from Telkom and neither the contact details of a person who can assist us with one. This is ridiculous! Should we do Telkom a favour and give them a bad credit record because they did not refund the R9.44 more than a year later? Would that make them update the credit records and give us the paid up letter we need?! We can not even get a reference number for the query for the paid up letter.