✅ Extracting max number from 2D array?

using System;

namespace Coding.Exercise
{
    public class Exercise
    {
        public static int FindMax(int[,] numbers)
        {
            int max = 0;
            var height = numbers.GetLength(0);
            if(height == 0){
                return -1;
            }
            var width = numbers.GetLength(1);
            if(width ==  0){
                return -1;
            }
            for(int i = 0; i < height; i++){
                for(int j = 0; j < width; j++){
                    if(numbers[i,j] < max){
                        max = numbers[i,j];
                    }
                }
            }
            return max;
        }
    }
}