TPN wrongly place a black mark for rent that was paid on time

TPN Systems / Properties have posted on my credit record that I am in arrears for my Sept Rental. I now have a black mark against my record and have been defamed as my rent was paid on time. I have queried this but have been unable to talk to anyone as the telephone number give for me to contact them, 031 0351871 says the subscriber is unavailable. What is the point of a contact number that does not work unless it is to keep complainants from accessing staff. With any system which actually impacts seriously with people's reputations and their credit ability there must be checks and balances. At no time did TPN check with the landlord, the real estate agent or my self if the rent had been paid and what the situation was. They simply and wrongfully put a black mark against my name. They have now, after an e mail complaint, sent me an sms rectifying and confirming my rent was paid on time . That is insufficient and I need to know how this happened, what is being done to ensure this does not happen again and more importantly what action has been taken against the person who posted an incorrect report that has defamed me.