Ordered that the order dated February 13, 2015 is affirmed, with costs.

"Although a motion for leave to renew generally must be based on newly-discovered facts, this requirement is a flexible one, and a court has the discretion to grant renewal upon facts known to the movant at the time of the original motion, provided that the movant offers a reasonable justification for the failure to submit the additional facts on the original motion" (Matter of Allstate Ins. Co. v Liberty Mut. Ins., 58 A.D.3d 727, 728 [2009]; see Matter of Osorio v Motor Veh. Acc. Indem. Corp., 112 A.D.3d 831, 832-833 [2013]; Deutsche Bank Trust Co. v Ghaness, 100 A.D.3d 585, 586 [2012]; Dervisevic v Dervisevic, 89 A.D.3d 785, 786 [2011]; Gonzalez v Vigo Constr. Corp., 69 A.D.3d 565, 566 [2010]). What is considered a "reasonable justification" is within the Supreme Court's discretion (Heaven v McGowan, 40 A.D.3d 583, 586 [2007]; see Calle v Zimmerman, 133 A.D.3d 809 [2015]). "Law office failure can be accepted as a reasonable excuse in the exercise of the court's sound discretion" (Nwauwa v Mamos, 53 A.D.3d 646, 649 [2008]; see CPLR 2005; Rivera v Queens Ballpark Co., LLC, 134 A.D.3d 796 [2015]).

Here, contrary to the appellant's contention, the Supreme Court did not improvidently exercise its discretion in granting that branch of the plaintiff's motion which was for leave to renew his opposition to her motion, as the excuse of law office failure presented by the plaintiff was reasonable under the circumstances (see Gordon v Boyd, 96 A.D.3d 719, 720 [2012]; Matter of Beren v Beren, 92 A.D.3d 676, 677 [2012]; see also Hackney v Monge, 103 A.D.3d 844, 845 [2013]).

Furthermore, upon renewal, considering all the circumstances of this case, the Supreme Court providently exercised its discretion in denying the appellant's motion pursuant to CPLR 3012 (b) to dismiss the complaint insofar as asserted against her for failure to serve a timely complaint. The plaintiff proffered a reasonable excuse for his delay in serving the complaint after being served by the appellant with a notice of appearance and demand for a complaint, and established that he had a potentially meritorious cause of action against the appellant (see Mitrani Plasterers Co., Inc. v SCG Contr. Corp., 97 A.D.3d 552, 552-553 [2012]).

The appellant's remaining contentions are either without merit or improperly raised for the first time on appeal.