BEING HARASSED BY DALY CREDIT BUREAU FOR MR PRICE MOBILE PAID UP ACCOUNT

I am receiving almost daily emails threatening me with legal action for a Mr Price Mobile account that I have paid up over 1 year ago. This is the second credit bureau trying to collect money I do not owe. In order to avoid continual phone calls and mails, I sent them the proof of EFT payments and the mails between myself and Mr Price Mobile (whose accounting system is terrible), one of which confirms that my account is up to date and another confirming that the contract is cancelled. Between the credit bureau and Mr Price Mobile they do not seem to understand that a debit order that is reversed is not the same as being unpaid due to insufficient funds. Mr Price Mobile continued to debit my account with various amounts after the contract period had terminated and these debit orders were reversed. There must be somewhere this can be reported as it is now becoming ridiculous that they cannot seem to understand that the account is paid up and the contract is terminated. I have reams of correspondence and EFT proof that this is in fact so.