Index: ssts-invoice/src/main/java/com/forgon/disinfectsystem/invoicemanager/service/InvoiceOptimizeManagerImpl.java
===================================================================
diff -u -r28490 -r28492
--- ssts-invoice/src/main/java/com/forgon/disinfectsystem/invoicemanager/service/InvoiceOptimizeManagerImpl.java	(.../InvoiceOptimizeManagerImpl.java)	(revision 28490)
+++ ssts-invoice/src/main/java/com/forgon/disinfectsystem/invoicemanager/service/InvoiceOptimizeManagerImpl.java	(.../InvoiceOptimizeManagerImpl.java)	(revision 28492)
@@ -1158,9 +1158,12 @@
 	 */
 	private Map<Long , List<TousseInstance>> getAllNotSentForeignTousseAppIdToForeignTousseInstanceListMap(List<Long> invoicePlanIdList){
 		List<TousseInstance> tousseInstanceList = tousseInstanceManager.getNotSentTousseInstanceListByForeignTousseApplicationIdListForInvoice(invoicePlanIdList);
-		Map<Long , List<TousseInstance>> invoicePlanIdToAllTiListMap = 
-				tousseInstanceList.stream().collect(Collectors.groupingBy(TousseInstance::getForeignTousseApp_id));
-		return invoicePlanIdToAllTiListMap;
+		if(CollectionUtils.isNotEmpty(tousseInstanceList)){
+			Map<Long , List<TousseInstance>> invoicePlanIdToAllTiListMap = 
+					tousseInstanceList.stream().collect(Collectors.groupingBy(TousseInstance::getForeignTousseApp_id));
+			return invoicePlanIdToAllTiListMap;
+		}
+		return null;
 	}
 
 	/**