Ni act complaint dd

Absence of complainant (not plaintiff) is no ground for dismissal of the complaint.

You may file an application before the (same) court to recall its order and restore the  complaint at its original stage.

Since criminal court can't recall it's order so you have to file revision u/sec 397 Cr.P.C ( 438 BNSS ) before Session Judge to get set aside dismissal order.

Once a Magistrate passes an order dismissing the complaint and acquitting the accused, they become functus officio (their official authority on that specific matter has ended). Under criminal law, a Magistrate does not have the inherent power to review or recall their own final order. Filing a "restoration application" in the same Trial Court is rejected on these grounds.

Actually this dismissal is treated as an acquittal of the accused in the case. Therefore you can file an Appeal Against Acquittal in the High Court having jurisdiction over the trial court.  You can file a petition under  Section 378(4) of the CrPC. Along with your appeal, you must file an application for Special Leave to Appeal. 

In your application, you must provide a solid, justifiable reason for your (or your advocate's) absence on that specific day (e.g., medical emergency, misleading dates, lack of proper notice). If the High Court finds the explanation genuine and believes that dismissing the case without a trial on the merits would cause grave injustice, it will set aside the Magistrate's order and direct the trial court to restore and resume the case.

Your appeal before Sessions Court is maintainable under Proviso to Section 372 CrPC as victim in this case. 

Let your lawyer may file an appeal.

It is still an usettled question whether the complainant in a case under Negotiable Instrument Act is a "victim" as contemeplated under Section 372 CrPC.