Unmanaged default list

I had an account with NWJ, not even once had I missed the payment, but they put my name on default list. I consulted them about this and I have statements to prove it, they did not even apologies. I have paid off this account in April and asked them to close it, they have not done that. They are not a store to have a relationship with, they can mess up your credit record for no reason and they don’t care how sensitive your credit record is.