Data not supplied? updated with string str being edited

See more:

C#

XML

Hi i been trying to save my data into the database but it seem that problem is that the orderID and OrderDate and CustomerID is not suppiled. But i do not know why?
The error keep saying The parameterized query '(@orderId nvarchar(4000),@customerId nvarchar(4000),@orderDate n' expects the parameter '@orderId', which was not supplied.

this us my xml file that i trying to store in the database(using Vs builtin database)

<Order Order_ID="1" Order_Date="1/2/2013" Buyer_ID="GFS1810">
  <Remark />
  <Item Item_ID="123" Size="M" Color="blue" Quantities="10" ePrice="33.77">Very Nice</Item>

my xml code

XmlNodeList nodelist = xmlDoc.GetElementsByTagName("Order");
foreach (XmlNode onode in nodelist)
{
    if (onode.Attributes.Count > 0)
    {
        textBox2.Text = "Order_ID = "+ onode.Attributes[0].Value + Environment.NewLine;
        textBox2.Text += "Order_Date = " + onode.Attributes[2].Value + Environment.NewLine;
        textBox2.Text += "Buyer_ID = " + onode.Attributes[1].Value + Environment.NewLine;
    }
}

XmlNodeList savList = sav.GetElementsByTagName("Order");
            ArrayList sList = new ArrayList();
            Order o = new Order();
            foreach (XmlNode node in savList)
            {
                o = new Order();
                o.orderId = node.Attributes[0].Value;
                o.orderDate = node.Attributes[2].Value;
                o.customerId = node.Attributes[1].Value;
                sList.Add(o);
            }

this is my sql code

string strsql = "insert into [Order] (OrderID, CustomerID, OrderDate)" + "values (@orderId, @customerId,@orderDate);";
public void insertOrder(ArrayList olist)
        {
            SqlConnection conn = new SqlConnection();
            conn.ConnectionString = ConfigurationManager.ConnectionStrings["Sup_DB_1.Properties.Settings.Sup1ConnectionString"].ConnectionString;
            conn.Open();
            foreach (Order o in olist)
            {
                SqlCommand comm = new SqlCommand(strsql, conn);
                comm.Parameters.AddWithValue("@orderId", o.orderId);
                comm.Parameters.AddWithValue("@customerId", o.customerId);
                comm.Parameters.AddWithValue("@orderDate", o.orderDate);

                comm.ExecuteNonQuery();
            }
            conn.Close();
        }

this is my order class

class Order
    {
        private string OrderId;
        private string OrderDate = "00/00/0000";
        private string CustomerId;
        private string Instructions;

        public string orderId
        {
            get { return OrderId; }
            set { value = OrderId; }
        }

        public string orderDate
        {
            get { return OrderDate; }
            set { value = OrderDate; }
        }

        public string customerId
        {
            get { return CustomerId; }
            set { value = CustomerId; }
        }

        public string instructions
        {
            get { return Instructions; }
            set { Instructions = value; }
        }
 
    }