Look for mistakes and misinformation, especially on when and how you were notified. If you believe you were not given “due process” then you can file a motion for rehearing or motion to dismiss with the court.
If you can prove that you were not given due process, the judge must consider your circumstances. It’s possible to have the case dismissed. Unless you are very comfortable with filing pro see (by yourself) I highly encourage you to discuss your case with an attorney well versed in credit and debt consumer law.