Order unanimously reversed, on the law and facts, without costs, defendant's motion denied, and verdict reinstated. Memorandum: The court erred in setting aside the verdict of no cause for action in favor of defendant. Plaintiff failed to plead or prove compliance with the written notice provision contained in the city charter (Niagara Falls City Charter, § 323-b), a condition precedent to bringing an action to recover for injuries incurred because of a defective or unsafe sidewalk. Additionally, plaintiff failed to establish that the condition of the sidewalk was caused by any affirmative act of the city ( Martin v City of Cohoes, 37 N.Y.2d 162, 166; Shaw v City of Auburn, 91 A.D.2d 817, affd 59 N.Y.2d 780).