Ask a Lawyer and Get Answers to Your Legal Questions
While we cannot draft your motion for you here (we can only offer "general legal information" we cannot practice law), I can point you in the direction of some helpful resources to get you started.
The Sacramento Law Library has a helpful publication/template for a Motion to Vacate: http://saclaw.org/wp-content/uploads/sbs-relief-from-default-judgment.pdf.
Their motion is based on the defendant's failure to file a response (as opposed to the plaintiff's failure to serve), but the same format, and same general principles apply. The only difference is going to be the legal basis for the motion is different (improper or fraudulent service), and the fact pattern will support that.
You can also visit your local law library - look specifically for a civil procedure practice guide (I recommend the "Rutter Guide, Civil Procedure Before Trial" in particular), as many of these guides have not only legal strategies, commonly used authorities, but will also have additional templates for motions and pleading papers to assist you.