How to remove parent child relationship

Content

Hi All,

I Have a requirement like under contact i can add no of products(product object is custom object here), same product may be linked with another contact, this is happening through report. now in first contact i want to remove association of the product, for this i have created a button on products report through report control addin. when i click on this button just i want to null contact id at product record to null. below is the code but that does not working .

Code Snippet

             using System;
using System.Collections.Generic;
using RightNow.AddIns.AddInViews;
using ReportComand_for_delete.ServiceReference1;
using System.Windows.Forms;
using RightNow.AddIns.Common;
using System.Drawing;
using System.AddIn;
using System.Net;


namespace ReportComand_for_delete
{
    [AddIn("delete")]
    public class Class1:IReportCommand2

    {
        private IGlobalContext gcontext;
        private IRecordContext rcontext;
        private static RightNowSyncPortClient _service;
        string prodID;
       
        string contId;