why web service parameter null?

Question

i have this web service 

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.Services;

using System.Web.Services.Protocols;

using System.Web.Services.Description;

using System.Xml;

namespace SDPReceiverWebService

{

    /// <summary>

    /// Summary description for RecieveSMS

    /// </summary>

    [WebService(Namespace = "http://www.csapi.org/wsdl/parlayx/sms/receive/v2_2/service")]

    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]

    [System.ComponentModel.ToolboxItem(false)]

    [SoapDocumentService(RoutingStyle = SoapServiceRoutingStyle.SoapAction)]

    // To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line. 

    // [System.Web.Script.Services.ScriptService]

    public class RecieveSMS : System.Web.Services.WebService

    {

        [WebMethod]

        public string HelloWorld()

        {

            //ReceiveSmsManager.ReceiveSmsService f = new ReceiveSmsManager.ReceiveSmsService();

            //f. = "sd";            

            Utility.WriteLogFile.WriteToLogFile("webService", "notifySmsReception", "hello");

            return "Hello World";

        }

      

        [WebMethod]

        [SoapDocumentMethod("syncOrderRelation", ParameterStyle = SoapParameterStyle.Wrapped, Use = SoapBindingUse.Literal,

            RequestNamespace = "http://www.csapi.org/schema/parlayx/data/sync/v1_0/local")]

        public DataSyncManager.syncOrderRelationResponse syncOrderRelation(DataSyncManager.syncOrderRelation syncOrderRelation)

        {

            DataSyncManager.syncOrderRelationResponse syncOrderResponse = new DataSyncManager.syncOrderRelationResponse();

            syncOrderResponse.resultDescription = "OK";

            syncOrderResponse.result = 0;

            try

            {

                string message = "effectiveTime: " + syncOrderRelation.effectiveTime;

                message += ", expiryTime: " + syncOrderRelation.expiryTime;

                message += ", productID: " + syncOrderRelation.productID;

                message += ", serviceID: " + syncOrderRelation.serviceID;

                message += ", serviceList: " + syncOrderRelation.serviceList;

                message += ", spID: " + syncOrderRelation.spID;

                message += ", updateDesc: " + syncOrderRelation.updateDesc;

                message += ", updateTime: " + syncOrderRelation.updateTime;

                message += ", updateType: " + syncOrderRelation.updateType.ToString();

                message += ", userID.ID: " + syncOrderRelation.userID.ID;

                message += ", userID.type: " + syncOrderRelation.userID.type.ToString();

                DataSyncManager.NamedParameter[] namedParams = syncOrderRelation.extensionInfo;

                if (namedParams != null)

                {

                    string namedParamsValue = "";

                    for (int i = 0; i < namedParams.Length; i++)

                    {

                        if (string.IsNullOrEmpty(namedParamsValue))

                        {

                            namedParamsValue += "Key: " + namedParams[i].key + ", value: " + namedParams[i].value;

                        }

                        else

                        {

                            namedParamsValue += "<br>Key: " + namedParams[i].key + ", value: " + namedParams[i].value;

                        }

                    }

                    message += ", extensionInfo: " + namedParamsValue;

                }

                Utility.WriteLogFile.WriteToLogFile("webService", "notifySmsReception", message);

                return syncOrderResponse;

            }

            catch (Exception ex)

            {

                syncOrderResponse.resultDescription = ex.Message;

                syncOrderResponse.result = -1;

                Utility.WriteLogFile.WriteToLogFile("webService", "notifySmsReception", ex.Message);

                return syncOrderResponse;

            }

        }

    }

}

i call it with this data 

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" 

xmlns:loc="http://www.csapi.org/schema/parlayx/data/sync/v1_0/local"> 

<soapenv:Header/> 

<soapenv:Body> 

<loc:syncOrderRelation> 

<loc:userID> 

<ID>254721214848</ID> 

<type>0</type> 

</loc:userID> 

<loc:spID>601399</loc:spID> 

<loc:productID>MDSP2000052892</loc:productID> 

<loc:serviceID>6013992000001442</loc:serviceID> 

<loc:serviceList>601399200000144</loc:serviceList> 

<loc:updateType>1</loc:updateType> 

<loc:updateTime>20120621232135</loc:updateTime> 

<loc:updateDesc>Addition</loc:updateDesc> 

<loc:effectiveTime>20120622001311</loc:effectiveTime> 

<loc:expiryTime>20120822001311</loc:expiryTime> 

<loc:extensionInfo> 

<namedParameters> 

<key>TransactionID</key> 

<value>1339730498361</value> 

<key>orderKey</key> 

<value>999000000009508556</value> 

<key>MDSPSUBEXPMODE</key> 

<value>1</value> 

<key>objectType</key> 

<value>1</value> 

<key>TraceUniqueID</key> 

<value>06212031580010010012</value> 

<key>rentSuccess</key> 

<value>false</value> 

</namedParameters> 

</loc:extensionInfo> 

</loc:syncOrderRelation> 

</soapenv:Body> 

</soapenv:Envelope>

why is the syncOrderRelation parameter null inside the syncOrderRelation method?