Task 7 multiarrays

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

//* Write a program that finds the largest area of equal neighbor elements
//in a rectangular matrix and prints its size. Example:

class LargestMatrizArea
{
    static void Main()
    {
        int[,] matrix = {
        {1,3,3,4,2,2,3,3,5},
        {3,2,2,3,4,2,3,5,5},
        {3,3,3,4,2,2,2,2,3},
        {2,3,2,3,3,1,1,5,5},
        {3,2,1,1,1,1,1,3,3}
        };
        //int midResult = 0;
        int maxiSize = 0;
        for (int row = 0; row < matrix.GetLength(0); row++)
        {
            for (int col = 0; col < matrix.GetLength(1); col++)
            {
                int midResult = 0;
                if (matrix[row,col] != -1)
                {
                    midResult = CheckCellResult(row,col,matrix);
                }
                if (midResult > maxiSize) maxiSize = midResult;
            }
        }
        Console.WriteLine(maxiSize);
    }

    static int CheckCellResult(int row, int col, int[,] matrix)
    {
        bool isAvailable = true;
        int midSize = 1;
        int simbol = matrix[row,col];
        matrix[row, col] = -1;
        while(isAvailable)
        {
            isAvailable = false;
            if (row > 0 && matrix[row - 1, col] == simbol)
            {
                midSize += CheckCellResult(row - 1, col, matrix);
                isAvailable = true;
            }
            else if (row > 0 && col> 0 && matrix[row - 1, col-1] == simbol)
            {
                midSize += CheckCellResult(row - 1, col-1, matrix);
                isAvailable = true;
            }
            else if (col > 0 && matrix[row, col - 1] == simbol)
            {
                midSize += CheckCellResult(row, col - 1, matrix);
                isAvailable = true;
            }
            else if (col > 0 && row < matrix.GetLength(0)-1 && matrix[row+1, col - 1] == simbol)
            {
                midSize += CheckCellResult(row+1, col - 1, matrix);
                isAvailable = true;
            }
            else if (row < matrix.GetLength(0) - 1 && matrix[row + 1, col] == simbol)
            {
                midSize += CheckCellResult(row + 1, col, matrix);
                isAvailable = true;
            }
            else if (col < matrix.GetLength(1)-1 && row > 0 && matrix[row - 1, col + 1] == simbol)
            {
                midSize += CheckCellResult(row - 1, col + 1, matrix);
                isAvailable = true;
            }
            else if (col < matrix.GetLength(1) - 1 && row < matrix.GetLength(0) - 1 && matrix[row + 1, col + 1] == simbol)
            {
                midSize += CheckCellResult(row + 1, col + 1, matrix);
                isAvailable = true;
            }
            else if (col < matrix.GetLength(1) - 1 && matrix[row, col + 1] == simbol)
            {
                midSize += CheckCellResult(row, col + 1, matrix);
                isAvailable = true;
            }
        }
        return midSize;
    }
}