You needn't post your question two times. Someone will respond when posted in the proper category. I responded to this question with your other post.
The court rules of civil procedure allow someone to be served by a substituted method when the party can't be found or appears to be avoiding the process server. It is perfectly acceptable to have a form of service in which you as the Defendant, don't actually receive notice of a lawsuit. All the creditor must do is comply with the court rules for trying to find you. Hope this perspective helps!
You should consult a lawyer. If you were not served, the only way that you can prevent a default is to make a motion to set aside the default, and you must do this promptly. Otherwise, you will lose your right to contest the debt.