Не могу разобраться с ошибками CS0501 CS0103

    using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace Arkanoid2
{
    public partial class FormGame : Form
    {
        static Random rnd = new Random();
        int racket_x, racket_y;
        int racket_shift_x = 8;
        int ball_x, ball_y;
        int ball_shift_x = 4; // max ball shift
        int ball_shift_y = 3;
        int ball_sx,      // current ball shift
            ball_sy;
        int side_lx,// left x
            side_rx,// right x
            side_uy;// up y
        int total_bricks;

        private static Timer atimer;
        public FormGame()
        {
            InitializeComponent();
        }

        private void FormGame_Shown(object sender, EventArgs e)
        {
            init_game();
        }
        private void init_game()
        {
            racket_x = racket.Location.X;
            racket_y = racket.Location.Y;
            side_lx = label_left.Location.X + label_left.Width;
            side_rx = label_right.Location.X;
            side_uy = label_top.Location.X + label_top.Height;
            ball_x = ball.Location.X;
            ball_y = ball.Location.Y;
            ball_sx = ball_shift_x;
            ball_sy = -ball_shift_y;
            total_bricks = 5;
        }
        private void FormGame_KeyDown(object sender, KeyEventArgs e)
        {
            Keys key = e.KeyCode;
            switch (key)
            {
                case Keys.Left: shift_racket(-racket_shift_x); break;
                case Keys.Right: shift_racket(racket_shift_x); break;
                case Keys.Enter: timer.Enabled = true; break;
            }
        }
        private void shift_racket(int sx)
        {
            int ax1 = racket_x += sx;
            int ax2 = ax1 + racket.Width;
            if (side_lx > ax1) ax1 = side_lx;
            if (side_rx < ax2) ax1 = side_rx - racket.Width;
            racket_x = ax1;
            racket.Location = new Point(racket_x, racket_y);
        }
        private void move_ball()
        {
            int bx1, by1,
                bx2, by2;
            bx1 = ball_x;
            bx2 = ball_x + ball.Width;
            by1 = ball_y;
            by2 = ball_y + ball.Height;
            if (bx1 + ball_sx < side_lx)
                ball_sx = ball_shift_x + rnd.Next(-1, 2);
            if (bx2 + ball_sx > side_rx)
                ball_sx = -ball_shift_x + rnd.Next(-1, 2);
            if (by1 + ball_sy < side_uy)
                ball_sy = ball_shift_y + rnd.Next(-1, 2);
            if (by2 + ball_sy > racket_y)
            {
                int bx0, by0;
                bx0 = (bx1 + bx2) / 2;
                by0 = (by1 + by2) / 2;
                int rx1, rx2;
                rx1 = racket_x;
                rx2 = racket_x + racket.Width;
                if (rx1 <= bx0 && bx0 <= rx2)
                {
                    ball_sy = -ball_shift_y + rnd.Next(-1, 2);
                }
                else
                    if (rx1 <= bx2 + ball.Width && bx2 + ball.Width <= rx2)
                {
                    ball_sy = -ball_shift_y + rnd.Next(-1, 2);
                    ball_sx = -ball_shift_x + rnd.Next(-1, 2);
                }
                else
                    if (rx1 <= bx1 - ball.Width && bx1 - ball.Width <= rx2)
                {
                    ball_sy = -ball_shift_y + rnd.Next(-1, 2);
                    ball_sx = ball_shift_x + rnd.Next(-1, 2);
                }
                else
                    lose_ball();
            }
            ball_x += ball_sx;
            ball_y += ball_sy;
            ball.Location = new Point(ball_x, ball_y);
            cross_brick(brick1);
            cross_brick(brick2);
            cross_brick(brick3);
            cross_brick(brick4);
            cross_brick(brick5);
        }
        private void timer1_Tick(object sender, EventArgs e)
        {
            cont_brick();
        }
        private void timer_Tick(object sender, EventArgs e)
        {
            move_ball();
        }
        private void lose_ball()
        {
            timer.Enabled = false;
            MessageBox.Show("LOST");
            DialogResult = System.Windows.Forms.DialogResult.Abort;
        }
        private void cross_brick(Label brick)
        {
            if (!brick.Visible) return;
            int bx1, bx0, bx2,
                by1, by0, by2;
            int rx1, rx2,
                ry1, ry2;
            bx1 = ball_x;
            bx2 = ball_x + ball.Width;
            bx0 = (bx1 + bx2) / 2;
            by1 = ball_y;
            by2 = ball_y + ball.Height;
            by0 = (by1 + by2) / 2;
            rx1 = brick.Location.X;
            rx2 = rx1 + brick.Width;
            ry1 = brick.Location.Y;
            ry2 = ry1 + brick.Height;
            if (rx1 <= bx0 && bx0 <= rx2 &&
                ry1 <= by2 && by2 <= ry2)
            {
                drop_brick(brick);
                ball_sy = -ball_sy;
                return;
            }
            if (rx1 <= bx2 && bx2 <= rx2 &&
                ry1 <= by0 && by0 <= ry2)
            {
                drop_brick(brick);
                ball_sx = -ball_sx;
                return;
            }
            if (rx1 <= bx1 && bx1 <= rx2 &&
               ry1 <= by0 && by0 <= ry2)
            {
                drop_brick(brick);
                ball_sx = -ball_sx;
                return;
            }

            if ((rx1 <= bx2 && bx2 <= rx2 && ry1 <= by2 && by2 <= ry2) ||
             (rx1 <= bx1 && bx1 <= rx2 && ry1 <= by2 && by2 <= ry2) ||
             (rx1 <= bx1 && bx1 <= rx2 && ry1 <= by1 && by1 <= ry2) ||
             (rx1 <= bx2 && bx2 <= rx2 && ry1 <= by1 && by1 <= ry2))

            {
                drop_brick(brick);
                ball_sx = -ball_sx;
                ball_sy = -ball_sy;
                return;
            }
        }
        private void drop_brick(Label brick)
        {
            brick.Visible = false;
            total_bricks--;
            if (total_bricks == 0)
            {
                timer.Enabled = false;
                MessageBox.Show("WIN!!!!");
                DialogResult = System.Windows.Forms.DialogResult.OK;
            }
        }

        private void end_brick(Label brick);
        {
           if(brick1 =)

         }

        private void last_brick()
        {
            atimer= new System.Windows.Forms.Timer();
            atimer.Interval = 10000;

            if (total_bricks == 1) ;
            {
                atimer.Enabled = true;
             }
            if (atimer.Interval == 0) ;
            {
                timer1.Enabled = true;
            }

        }
    }
}

Не могу разобраться с кодом у меня выскакивает ошибка CS0103 CS0103 The name 'cont_brick' does not exist in the current context то же самое относится и к "atimer" . Прошу помощи.