soap:MustUnderstand System.Web.Services.Protocols.SoapHeaderException: SOAP header RequiredServiceHeader was not understood. at System.Web.Services.Protocols.SoapHeaderHandling. EnsureHeadersUnderstood(SoapHeaderCollection headers) at System.Web.Services.Protocols.SoapServerProtocol. WriteReturns(Object[] returnValues, Stream outputStream) at System.Web.Services.Protocols. WebServiceHandler.WriteReturns(Object[] returnValues) at System.Web.Services.Protocols. WebServiceHandler.Invoke()