Bad Administration (Credit Management)

I have been accused of having defaulted on a payment for a product I cancelled within the 7 day cool off period. Last year it resulted me being handed over prematurely when your systems did not reflect the cancellation on time. I was told this matter would be escalated to the credit management department last year June - July. this year I app**** for a homeloan and I was told that there is a finding against my name lodged by telkom. I am now being asked to provide proof that I owe nothing. this shoudl not have been the case as this matter in my mind was resolved last year. Sadly I am now in the position where I may not get the funding I asked for because of an error Telkoms part. I want a letter from Tlkom confirm I owe nothing and furhthermore I need a letter stating that no demand for any funds were ever made against me and that I was never handed over. I also require proof that this doesn't reflect on my credit record. If I do not get this I will have no other recourse but to seek further legal assistance to remedy this matter.