Rule 4 does apply. If the Defendants were not served with both the summons and original complaint within 120 days you may do one of two things:
1) dismiss the case without prejudice (ensure the dismissal is without prejudice), and file a new lawsuit. Then serve the defendants with a new summons and complaint.
2) Petition the court in a motion to allow you to serve the defendants after the 120 days has passed showing "good cause" as to why you did not serve in the allotted time. Rule 4(m) allows for this exception. You can point to the fact that the Defendants have appeared in the action to oppose the service if it is helpful to your motion.
I cannot advise you as to your case, but I will note, if you are running up against the statute of limitations
, be very careful. If you dismiss your case and refile, and your statute of limitations has run prior to the date of your new case, you will lose based on the necessity to refile. (if this is the case, include it in your motion under option 2).
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