Interest charged on cancelled & I overpaid account

I took Telkom internet account in Feb 2015 and by April i still havent received statements to show how much i must pay I called Telkom and gave them my email address to send me statements by June 2015 I still havent received any statement I called again i was told my information has been updated but i still could not receive statement. End of August 2015 my account was suspended and closed and i phoned I was told i need to pay I ASKED for details to go and pay I was still not given them, I received letter from Telkom lawyers that I owe R1495, I paid R500 in Sept and R1300 in Oct 2015. Called Telkom again to try to get my internet account activated I was transfered to pillar and post and finally told that my account has been cancelled and suspended it cannot be activated. I send the proof of payment to their lawyer who sent me the letter that i owe R1495 in August and told her that i paid R1800 to my suprise today i get sms that my name is in credit bureau. AFTER ALL MY EFFORTS CALLING TELKOM ASKING FOR ACCOUNT NUMBER I PAY AS PER LETTER FROM THEIR LAWYERS I STILL GET MY NAME LISTED HOW UNFAIR IS THIS. TELKOM CANNOT CONTINUE TO CHARGE ME EXORBITANT INTEREST WHILE THEY TERMINATED IT