Legal Question in Bankruptcy in California

Bankruptcy might permanently or temporarily stop the garnishment, depending on the reason for the underlying lawsuit.

Because you claim you were never served, you can file a motion in state court to set aside the default and judgment, and hear the case. Of course, if you owe the debt, that would be a futile and expensive act. It would, however, put you in a better bargaining position, and you might even have some defenses such as running of the statute of limitation.