diff --git a/tests/system-test/7-tmq/tmqConsumeDiscontinuousData.py b/tests/system-test/7-tmq/tmqConsumeDiscontinuousData.py
index 3dabca4cd1..dd2420dcfb 100644
--- a/tests/system-test/7-tmq/tmqConsumeDiscontinuousData.py
+++ b/tests/system-test/7-tmq/tmqConsumeDiscontinuousData.py
@@ -205,12 +205,21 @@ class TDTestCase:
         time.sleep(self.walRetentionPeriod + 1)
         tdLog.info("secondely call to flash database")
         tdSql.query("flush database %s"%(paraDict['dbName']))
-        
+
         # wait the consumer to complete one poll
         while (0 == self.retryPoll):
             time.sleep(1)
             continue
-        
+
+        # write data again when consumer stopped to make sure some data aren't consumed
+        pInsertDataAgainThread = tmqCom.asyncInsertDataByInterlace(paraDict)
+        pInsertDataAgainThread.join()
+        tdLog.info("firstly call to flash database when writing data second time")
+        tdSql.query("flush database %s"%(paraDict['dbName']))
+        time.sleep(self.walRetentionPeriod + 1)
+        tdLog.info("secondely call to flash database when writing data second time")
+        tdSql.query("flush database %s"%(paraDict['dbName']))
+
         with self.lock:
             self.retryPoll = 0            
             currentTime = datetime.now()      
@@ -218,15 +227,14 @@ class TDTestCase:
         
         paraDict["startTs"] = 1640966400000 + paraDict["ctbNum"] * paraDict["rowsPerTbl"]
         pThread3 = tmqCom.asyncInsertDataByInterlace(paraDict)
-        
-                
+
         tdLog.debug("wait sub-thread to end insert data")        
         pThread3.join()
-        
-        totalInsertRows = paraDict["ctbNum"] * paraDict["rowsPerTbl"] * 2
+
+        totalInsertRows = paraDict["ctbNum"] * paraDict["rowsPerTbl"] * 3
         tdLog.debug("wait sub-thread to end consume data")
         pThread2.join()
-        
+
         tdLog.info("act consume total rows: %d, act insert total rows: %d"%(self.actConsumeTotalRows, totalInsertRows))
         
         if (self.actConsumeTotalRows >= totalInsertRows):