CPC Section 99 - No decree to be reversed or modified for error or irregularity not affecting merits or jurisdiction

No decree shall be reversed or substantially varied, nor shall any case be remanded in appeal on account of any misjoinder or non-joinder of parties or causes of action or any error, defect or irregularity in any proceedings in the suit, not affecting the merits of the case or the jurisdiction of the Court;

Provided that nothing in this section shall apply to non-joinder of a necessary party.