SPListItem not updating?

private bool SyncingProcess(SqlDataReader d, SPList UserInfoList)
        {
            bool result =false;
            try
            {            //-->
                SPListItem UILUser = null;
                // Build a query.
                SPQuery query = new SPQuery();
                query.Query = string.Concat( "<Where><Eq>","<FieldRef Name='Name'/>",
                    "<Value Type='Text'>" +(d.IsDBNull(accountIDPOS) == false
                         ? d.GetString(accountIDPOS)
                         : "information not found") + "</Value>",
                    "</Eq></Where>");

                query.ViewFields = string.Concat("<FieldRef Name='FirstName' />","<FieldRef Name='LastName' />",
                    "<FieldRef Name='Email' />","<FieldRef Name='FullName' />","<FieldRef Name='Title' />",
                    "<FieldRef Name='JobTitle' />");

                SPListItemCollection userInfoListitems = UserInfoList.GetItems(query);
                if (userInfoListitems != null && userInfoListitems.Count > 0)
                {
				    UILUser = userInfoListitems[0];
                    SPUser user1 = UILUser.Web.EnsureUser("aspnetsqlmembershipprovider:" + d.GetString(accountIDPOS));                  
                    if (UILUser != null)
                    {  
					    UILUser["FirstName"] = (d.IsDBNull(FIRSTNAMEPOS) == false ? d.GetString(FIRSTNAMEPOS) : "");                           
                        UILUser["LastName"] = (d.IsDBNull(LASTNAMEPOS) == false ? d.GetString(LASTNAMEPOS) : "");
                        UILUser["Title"] = (d.IsDBNull(FULLNAMEPOS) == false ? d.GetString(FULLNAMEPOS) : "");
                        UILUser["EMail"] = (d.IsDBNull(EMAIL_ADDRESSPOS) == false? d.GetString(EMAIL_ADDRESSPOS): "");
                        UILUser["JobTitle"] = (d.IsDBNull(TITLEPOS) == false ? d.GetString(TITLEPOS) : "");
                        UILUser.Update();;
                        UserInfoList.Update();   
                    }
                    result =true;
                }
                else
                {
                    tw.WriteLine("User not found in the " + UserInfoList.ParentWeb.Title.ToString() + " Site " +
                                 (d.IsDBNull(FIRSTNAMEPOS) == false
                                      ? d.GetString(FIRSTNAMEPOS) + "; " + d.GetString(accountIDPOS)
                                      : "information not found"));
                    tw.Flush();
                }
               
            }
            catch (Exception)
            {
                result =false;
            }
            return result;
        }
    }
}