A small hiccup for the LeetCode puzzle Where the ball will fall

public class ZigZagBallFallsTry
{

    public int[] FindBall(int[][] grid)
    {
        int col = grid[0].Length-1;
        int row = grid.Length-1;
        int[] result = new int[col];

        for (int i = 0; i < col; i++)
        {
            result[i] = BallHelp(grid, row, col);
        }

        return result;

    }

    private int BallHelp(int[][] grid, int row, int col)
    {
        int currRow = 0;
        int currCol = col;

        while (currRow <= row)
        {
            if (grid[currRow][currCol] == 1)
            {
                if (currCol == col || grid[currRow][currCol + 1] == -1)
                {
                    return -1;
                }
                else
                {
                    currCol++;
                    currRow++;
                } 
            } 
            else if (grid[currRow][currCol] == -1)
            {
                if (currCol == 0 || grid[currRow][currCol - 1] == 1)
                {
                    return -1;
                }
                else
                {
                    currCol--;
                    currRow++;
                }
            } 
            else 
            {
                currRow++;
            }
        }

        return currCol;
    }

}