The motion court properly granted plaintiffs motion for reargument, since it had misapplied a "controlling principle of law" ( Foley v Roche, 68 AD2d 558, 567; see CPLR 2221 [d]). When dismissing the complaint as against appellants, the court improperly relied on the gap-in-treatment argument, which appellants raised for the first time in their reply papers ( see McNair v Lee, 24 AD3d 159). Indeed, the court determined that plaintiff had otherwise raised a triable issue of fact, but that her failure to address the gap in her treatment was "fatal" to her case.