Hello and thank you for your question.
You need to file an application in the relevant court to have the default judgment set aside and the reasons why it should be set aside, along with an affidavit confirming any facts relevant to the application.
Strict time limits generally apply, (e.g. in the magistrates court you have 21 days to apply to have a default judgment set aside:
I would strongly recommend that you engage a lawyer to assist you with such an application, however, as drafting the application and affidavit is not a straight forward matter. The Notice of Motion and Affidavit must be in the proper form, use proper pleadings and comply with the rules of evidence or it may be struck out on a technical basis, and you may only get one shot at drafting these documents. Moreover, if you are unsuccessful you will very likely be ordered to pay the other parties legal costs of your application in addition to the default judgment amount.
If you need help locating a suitable lawyer, contact the WA Law Society as they can refer you to suitable lawyers in your area:
I trust the above assists.
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