get Customer Cases not closed

@operator

I need to perform search based on Customer internal id and where status is not closed. The following code returns all cases (including status equal "Closed"). Why ???

 static SearchResult getCustomerCasesById(NetSuiteService service, string iternalId)          {              SupportCaseSearch casesearch = new SupportCaseSearch();                SearchMultiSelectField sm = new SearchMultiSelectField();              sm.@operator = SearchMultiSelectFieldOperator.anyOf;              sm.operatorSpecified = true;              sm.searchValue = new RecordRef[1];              sm.searchValue[0] = new RecordRef();              sm.searchValue[0].internalId = iternalId;                CustomerSearchBasic csb = new CustomerSearchBasic();              csb.internalId = sm;              casesearch.customerJoin = csb;                SearchMultiSelectField status = new SearchMultiSelectField();              status.@operator = SearchMultiSelectFieldOperator.noneOf;              status.operatorSpecified = true;              status.searchValue = new RecordRef[1];              status.searchValue[0] = new RecordRef();              status.searchValue[0].name = "Closed";              status.searchValue[0].internalId = "5";              status.searchValue[0].type = RecordType.account;                            IssueSearchBasic isb = new IssueSearchBasic();              isb.status = status;              casesearch.issueJoin = isb;                // perform case search based on Case Id where status is not closed...              return service.search(casesearch);                   }