Parameter @Item_code was not supplied something error

private void button3_Click(object sender, EventArgs e)
{                    
   try
   {
      for (int i = 0; i < dataGridView1.Rows.Count-1 ; i++)
      {
         BILLId();
         ID();
         SqlConnection con = new SqlConnection(@"Data Source=localhost;Initial Catalog=ParamBills;Persist Security Info=True;User ID=sa;Password=login");
         SqlCommand cmd = new SqlCommand("insert_Sales_Details", con);
         con.Open();

         cmd.CommandType = CommandType.StoredProcedure;
         cmd.Parameters.Add("@id", SqlDbType.Int ).Value = textBox9.Text;
         cmd.Parameters.Add("@Bill_No", SqlDbType.NVarChar).Value = textBox8.Text;
         cmd.Parameters.Add("@SDate", SqlDbType.DateTime).Value = dateTimePicker1.Text;
         cmd.Parameters.Add("@Sales_Person", SqlDbType.NVarChar).Value = textBox6.Text;
         cmd.Parameters.Add("@Cashcounter_No", SqlDbType.NVarChar).Value = textBox7.Text;
         cmd.Parameters.Add("@Tax2", SqlDbType.Float).Value = textBox3.Text;
         cmd.Parameters.Add("@Sub_Total", SqlDbType.Float).Value = textBox10.Text;
         cmd.Parameters.Add("@Discount", SqlDbType.Float ).Value = textBox5.Text;
         cmd.Parameters.Add("@Total", SqlDbType.Float).Value = textBox2.Text;
         cmd.Parameters.Add("@Total2", SqlDbType.Float).Value = textBox4.Text;
         cmd.Parameters.Add("Total_Item", SqlDbType.Int).Value = textBox11.Text;
                              
         cmd.Parameters.Add("@Product_Code", SqlDbType.NVarChar).Value = dataGridView2.Rows[i].Cells[0].Value;
         cmd.Parameters.Add("@Product_Type", SqlDbType.NVarChar).Value = dataGridView2.Rows[i].Cells[1].Value;
         cmd.Parameters.Add("@Product_Type_Code", SqlDbType.NVarChar).Value = dataGridView2.Rows[i].Cells[2].Value;
         cmd.Parameters.Add("@Product_Name", SqlDbType.NVarChar).Value = dataGridView2.Rows[i].Cells[3].Value;
         cmd.Parameters.Add("@Item_Code", SqlDbType.NVarChar).Value = dataGridView2.Rows[i].Cells[4].Value;
         // cmd.Parameters.AddWithValue("@Item_Code", dataGridView2.Rows[i].Cells[4].Value);
         cmd.Parameters.Add("@Item_Name", SqlDbType.NVarChar).Value = dataGridView2.Rows[i].Cells[5].Value;
         cmd.Parameters.Add("@Qty", SqlDbType.Int).Value = dataGridView2.Rows[i].Cells[6].Value;
         cmd.Parameters.Add("@Tax", SqlDbType.Float).Value = dataGridView2.Rows[i].Cells[7].Value;
         cmd.Parameters.Add("@Selling_Price", SqlDbType.Float).Value = dataGridView2.Rows[i].Cells[8].Value;
         cmd.Parameters.Add("@Product_Price", SqlDbType.Float).Value = dataGridView2.Rows[i].Cells[9].Value;
                    
         cmd.ExecuteNonQuery();
         con.Close();
      }
      MessageBox.Show("Saved");
   }
   catch (Exception ex)
   {
      MessageBox.Show(ex.Message);
   }
}