If you think something is wrong with your credit report, the first step is to contact the relevant lender or credit reporting body and ask them to explain why the information is on your report. If the information is incorrect, it will be taken off or changed (depending on the circumstances). If they don’t agree that the information is incorrect, they will need to provide you with reasons.
The credit provider or credit reporting body must respond to you within 30 days – unless you agree to extend that period. Once the matter has been investigated, you must be provided with a written response indicating whether or not a correction will be made (and if not, why not). This will all be done for free.
Refer to https://www.creditsmart.org.au/manage-your-credit-report/fixing-errors-in-your-credit-report/ for more information.