Prove of payment

Hi i have a contract with Telkom,i was handed over to the attorneys due to a none payment,i made the arrangement with them and i paid the outstanding amount which was R2400..Now they are saying that i didn't pay the account and I've been sending them a prove of payment..I've got all the names and email addresses of the people whom i was sending the emails to..i pay my account every month now my account has been suspended and they are saying i am owing R2400..This thing has affected my credit score in a bad way..Can you kindly assist me regarding this