I am Joseph Machete I have a clothing store account at Woolworths retail South Africa I have been paying them for months now, but what I just realised is that my credit record is on a negative

I am Joseph Machete I have a clothing store account at Woolworths retail South Africa I have been paying them for months now, but what I just realised is that my credit record is on a negative. They always quick to hand my account over, but when they receive payment they don’t go back to update the accounts. Yesterday I was buying a car I was told that I am behind with three months and have missed three months payment which is not true. I tried to call them no one answered the call, I went to the store a lady that they referred me at the store to help me refused to help me. And this is affecting my credit score and my account with them is updated long time but they don’t take effort to rectify that with the bureau.