diff --git a/tests/pytest/client/change_time_1_1.py b/tests/pytest/client/change_time_1_1.py
index 32917ab2e4..1744c09132 100644
--- a/tests/pytest/client/change_time_1_1.py
+++ b/tests/pytest/client/change_time_1_1.py
@@ -56,8 +56,8 @@ class TDTestCase:
         
         #move 5 days ahead to 2020/10/25. 4 oldest files should be removed during the new write
         #leaving 7 data files.
-        os.system ('timedatectl set-time 2020-10-25')
         try:
+            os.system ('timedatectl set-time 2020-10-25')
             os.system(f"{binPath}taosdemo -f tools/taosdemoAllTest/manual_change_time_1_1_B.json")
         except BaseException:
             os.system('sudo timedatectl set-ntp on')
@@ -78,6 +78,7 @@ class TDTestCase:
 
     def stop(self):
         os.system('sudo timedatectl set-ntp on')
+        tdLog.sleep(10)
         tdSql.close()
         tdLog.success("alter block manual check finish")
 
diff --git a/tests/pytest/client/change_time_1_2.py b/tests/pytest/client/change_time_1_2.py
index d693010be4..d8180136e6 100644
--- a/tests/pytest/client/change_time_1_2.py
+++ b/tests/pytest/client/change_time_1_2.py
@@ -54,8 +54,14 @@ class TDTestCase:
         else:
             tdLog.debug("data file number correct")
 
-        tdSql.query('select first(ts) from stb_0') #check the last data in the database
-        tdSql.checkData(0,0,datetime(2020,10,11,0,0,0,0))
+
+        try:
+            tdSql.query('select first(ts) from stb_0') #check the last data in the database
+            tdSql.checkData(0,0,datetime(2020,10,11,0,0,0,0))
+        except BaseException:
+            os.system('sudo timedatectl set-ntp on')
+            tdLog.sleep(10) 
+
 
         os.system ('timedatectl set-time 2020-10-25')
 
@@ -63,11 +69,17 @@ class TDTestCase:
         #4 oldest data file should be removed from tsdb/data
         #7 data file should be found 
         #vnode at TDinternal/community/sim/dnode1/data/vnode
-        os.system ('timedatectl set-time 2020-10-25')
-        tdDnodes.stop(1)
-        tdDnodes.start(1)
-        tdSql.query('select first(ts) from stb_0')
-        tdSql.checkData(0,0,datetime(2020,10,14,8,0,0,0)) #check the last data in the database
+
+        try:
+            os.system ('timedatectl set-time 2020-10-25')
+            tdDnodes.stop(1)
+            tdDnodes.start(1)
+            tdSql.query('select first(ts) from stb_0')
+            tdSql.checkData(0,0,datetime(2020,10,14,8,0,0,0)) #check the last data in the database
+        except BaseException:
+            os.system('sudo timedatectl set-ntp on')
+            tdLog.sleep(10) 
+
         os.system('sudo timedatectl set-ntp on')
         tdLog.sleep(10)
         commandArray = ['ls', '-l', f'{TDenginePath}/sim/dnode1/data/vnode/vnode2/tsdb/data']