You should have served your response by mail to the attorney of record or "pro per" when you filed your repsonse with the court. The 30 days was the time you had to file your response after service on you. If you have an insurance company for anything, especially auto, tender your defense immediately.
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you are suppoosed to serve your response by mail and then file it in the court house with a proof of service under penalty of perjury indicating that the response has been served. Consider hiring an attorney to assist you.
If you are talking about filing a cross-complaint against the defendant, that is filed at the same time you file your Answer to the Complaint. Your questions is a little confusing. If you were not served with the Complaint (properly) you can fight that as well. As my colleague has stated, you should send this to the insurance carrier for the car you were a passenger in and they should provide you with an attorney to represent you. Good luck.
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And if you do wish to challenge service, the motion must be your first appearance in the action (what is filed before the expiration of 30 days), or challenges on that ground are waived. As a practical matter, however, it's likely only a temporary solution, and could be a waste of time and expense, as the defendant will simply then serve you properly.
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