diff --git a/source/dnode/mnode/impl/inc/mndDef.h b/source/dnode/mnode/impl/inc/mndDef.h
index c83a40c25d..4656e0555f 100644
--- a/source/dnode/mnode/impl/inc/mndDef.h
+++ b/source/dnode/mnode/impl/inc/mndDef.h
@@ -99,6 +99,8 @@ typedef enum {
   TRN_CONFLICT_GLOBAL = 1,
   TRN_CONFLICT_DB = 2,
   TRN_CONFLICT_DB_INSIDE = 3,
+  TRN_CONFLICT_TOPIC = 4,
+  TRN_CONFLICT_TOPIC_INSIDE = 5,
 } ETrnConflct;
 
 typedef enum {
diff --git a/source/dnode/mnode/impl/src/mndConsumer.c b/source/dnode/mnode/impl/src/mndConsumer.c
index d5b7342768..2e78d03884 100644
--- a/source/dnode/mnode/impl/src/mndConsumer.c
+++ b/source/dnode/mnode/impl/src/mndConsumer.c
@@ -119,6 +119,27 @@ void mndRebCntDec() {
   }
 }
 
+static int32_t validateTopics(STrans *pTrans, const SArray *pTopicList, SMnode *pMnode) {
+  int32_t numOfTopics = taosArrayGetSize(pTopicList);
+
+  for (int32_t i = 0; i < numOfTopics; i++) {
+    char        *pOneTopic = taosArrayGetP(pTopicList, i);
+    SMqTopicObj *pTopic = mndAcquireTopic(pMnode, pOneTopic);
+    if (pTopic == NULL) {  // terrno has been set by callee function
+      return -1;
+    }
+
+    mndTransSetDbName(pTrans, pOneTopic, NULL);
+    if(mndTransCheckConflict(pMnode, pTrans) != 0){
+      mndReleaseTopic(pMnode, pTopic);
+      return -1;
+    }
+    mndReleaseTopic(pMnode, pTopic);
+  }
+
+  return 0;
+}
+
 static int32_t mndProcessConsumerRecoverMsg(SRpcMsg *pMsg) {
   SMnode                *pMnode = pMsg->info.node;
   SMqConsumerRecoverMsg *pRecoverMsg = pMsg->pCont;
@@ -142,10 +163,13 @@ static int32_t mndProcessConsumerRecoverMsg(SRpcMsg *pMsg) {
 
   mndReleaseConsumer(pMnode, pConsumer);
 
-  STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_RETRY, TRN_CONFLICT_NOTHING, pMsg, "recover-csm");
+  STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_RETRY, TRN_CONFLICT_TOPIC, pMsg, "recover-csm");
   if (pTrans == NULL) {
     goto FAIL;
   }
+  if(validateTopics(pTrans, pConsumer->assignedTopics, pMnode) != 0){
+    goto FAIL;
+  }
 
   if (mndSetConsumerCommitLogs(pMnode, pTrans, pConsumerNew) != 0) goto FAIL;
   if (mndTransPrepare(pMnode, pTrans) != 0) goto FAIL;
@@ -179,9 +203,11 @@ static int32_t mndProcessConsumerClearMsg(SRpcMsg *pMsg) {
 
   mndReleaseConsumer(pMnode, pConsumer);
 
-  STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_NOTHING, pMsg, "clear-csm");
+  STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_TOPIC, pMsg, "clear-csm");
   if (pTrans == NULL) goto FAIL;
-
+  if (validateTopics(pTrans, pConsumer->assignedTopics, pMnode) != 0){
+    goto FAIL;
+  }
   // this is the drop action, not the update action
   if (mndSetConsumerDropLogs(pMnode, pTrans, pConsumerNew) != 0) goto FAIL;
   if (mndTransPrepare(pMnode, pTrans) != 0) goto FAIL;
@@ -577,27 +603,6 @@ int32_t mndSetConsumerCommitLogs(SMnode *pMnode, STrans *pTrans, SMqConsumerObj
   return 0;
 }
 
-static int32_t validateTopics(const SArray *pTopicList, SMnode *pMnode, const char *pUser) {
-  int32_t numOfTopics = taosArrayGetSize(pTopicList);
-
-  for (int32_t i = 0; i < numOfTopics; i++) {
-    char        *pOneTopic = taosArrayGetP(pTopicList, i);
-    SMqTopicObj *pTopic = mndAcquireTopic(pMnode, pOneTopic);
-    if (pTopic == NULL) {  // terrno has been set by callee function
-      return -1;
-    }
-
-    if (mndCheckTopicPrivilege(pMnode, pUser, MND_OPER_SUBSCRIBE, pTopic) != 0) {
-      mndReleaseTopic(pMnode, pTopic);
-      return -1;
-    }
-
-    mndReleaseTopic(pMnode, pTopic);
-  }
-
-  return 0;
-}
-
 static void *topicNameDup(void *p) { return taosStrdup((char *)p); }
 
 static void freeItem(void *param) {
@@ -636,12 +641,12 @@ int32_t mndProcessSubscribeReq(SRpcMsg *pMsg) {
   }
 
   // check topic existence
-  pTrans = mndTransCreate(pMnode, TRN_POLICY_RETRY, TRN_CONFLICT_NOTHING, pMsg, "subscribe");
+  pTrans = mndTransCreate(pMnode, TRN_POLICY_RETRY, TRN_CONFLICT_TOPIC, pMsg, "subscribe");
   if (pTrans == NULL) {
     goto _over;
   }
 
-  code = validateTopics(pTopicList, pMnode, pMsg->info.conn.user);
+  code = validateTopics(pTrans, pTopicList, pMnode);
   if (code != TSDB_CODE_SUCCESS) {
     goto _over;
   }
diff --git a/source/dnode/mnode/impl/src/mndSubscribe.c b/source/dnode/mnode/impl/src/mndSubscribe.c
index 9579a18fc4..b4145ae8d0 100644
--- a/source/dnode/mnode/impl/src/mndSubscribe.c
+++ b/source/dnode/mnode/impl/src/mndSubscribe.c
@@ -553,13 +553,17 @@ static int32_t mndPersistRebResult(SMnode *pMnode, SRpcMsg *pMsg, const SMqRebOu
     }
   }
 
-  STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_DB, pMsg, "tmq-reb");
+  char topic[TSDB_TOPIC_FNAME_LEN] = {0};
+  char cgroup[TSDB_CGROUP_LEN] = {0};
+  mndSplitSubscribeKey(pOutput->pSub->key, topic, cgroup, true);
+
+  STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_TOPIC_INSIDE, pMsg, "tmq-reb");
   if (pTrans == NULL) {
     nodesDestroyNode((SNode*)pPlan);
     return -1;
   }
 
-  mndTransSetDbName(pTrans, pOutput->pSub->dbName, NULL);
+  mndTransSetDbName(pTrans, topic, cgroup);
   if (mndTransCheckConflict(pMnode, pTrans) != 0) {
     mndTransDrop(pTrans);
     nodesDestroyNode((SNode*)pPlan);
@@ -587,10 +591,6 @@ static int32_t mndPersistRebResult(SMnode *pMnode, SRpcMsg *pMsg, const SMqRebOu
     return -1;
   }
 
-  char topic[TSDB_TOPIC_FNAME_LEN] = {0};
-  char cgroup[TSDB_CGROUP_LEN] = {0};
-  mndSplitSubscribeKey(pOutput->pSub->key, topic, cgroup, true);
-
   // 3. commit log: consumer to update status and epoch
   // 3.1 set touched consumer
   int32_t consumerNum = taosArrayGetSize(pOutput->modifyConsumers);
@@ -802,6 +802,19 @@ static int32_t mndProcessDropCgroupReq(SRpcMsg *pMsg) {
     goto end;
   }
 
+  pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_TOPIC_INSIDE, pMsg, "drop-cgroup");
+  if (pTrans == NULL) {
+    mError("cgroup: %s on topic:%s, failed to drop since %s", dropReq.cgroup, dropReq.topic, terrstr());
+    code = -1;
+    goto end;
+  }
+
+  mndTransSetDbName(pTrans, dropReq.topic, dropReq.cgroup);
+  code = mndTransCheckConflict(pMnode, pTrans);
+  if (code != 0) {
+    goto end;
+  }
+
   void           *pIter = NULL;
   SMqConsumerObj *pConsumer;
   while (1) {
@@ -816,13 +829,6 @@ static int32_t mndProcessDropCgroupReq(SRpcMsg *pMsg) {
     sdbRelease(pMnode->pSdb, pConsumer);
   }
 
-  pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_NOTHING, pMsg, "drop-cgroup");
-  if (pTrans == NULL) {
-    mError("cgroup: %s on topic:%s, failed to drop since %s", dropReq.cgroup, dropReq.topic, terrstr());
-    code = -1;
-    goto end;
-  }
-
   mInfo("trans:%d, used to drop cgroup:%s on topic %s", pTrans->id, dropReq.cgroup, dropReq.topic);
 
   if (mndSetDropSubCommitLogs(pMnode, pTrans, pSub) < 0) {
diff --git a/source/dnode/mnode/impl/src/mndTopic.c b/source/dnode/mnode/impl/src/mndTopic.c
index cb18c0bc65..13c9b7d176 100644
--- a/source/dnode/mnode/impl/src/mndTopic.c
+++ b/source/dnode/mnode/impl/src/mndTopic.c
@@ -383,14 +383,15 @@ static int32_t mndCreateTopic(SMnode *pMnode, SRpcMsg *pReq, SCMCreateTopicReq *
   SQueryPlan *pPlan = NULL;
   SMqTopicObj topicObj = {0};
 
-  pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_DB, pReq, "create-topic");
+  pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_TOPIC, pReq, "create-topic");
   if (pTrans == NULL) {
     mError("topic:%s, failed to create since %s", pCreate->name, terrstr());
     goto _OUT;
   }
 
-  mndTransSetDbName(pTrans, pDb->name, NULL);
-  if (mndTransCheckConflict(pMnode, pTrans) != 0) {
+  mndTransSetDbName(pTrans, pCreate->name, NULL);
+  code = mndTransCheckConflict(pMnode, pTrans);
+  if (code != 0) {
     goto _OUT;
   }
   mInfo("trans:%d to create topic:%s", pTrans->id, pCreate->name);
@@ -661,6 +662,11 @@ static int32_t mndProcessDropTopicReq(SRpcMsg *pReq) {
   SMqTopicObj *pTopic = NULL;
   STrans      *pTrans = NULL;
 
+  if (!mndRebTryStart()) {
+    mInfo("mq rebalance already in progress, do nothing");
+    return 0;
+  }
+
   if (tDeserializeSMDropTopicReq(pReq->pCont, pReq->contLen, &dropReq) != 0) {
     terrno = TSDB_CODE_INVALID_MSG;
     code = -1;
@@ -680,14 +686,14 @@ static int32_t mndProcessDropTopicReq(SRpcMsg *pReq) {
     }
   }
 
-  pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_DB, pReq, "drop-topic");
+  pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_TOPIC, pReq, "drop-topic");
   if (pTrans == NULL) {
     mError("topic:%s, failed to drop since %s", pTopic->name, terrstr());
     code = -1;
     goto end;
   }
 
-  mndTransSetDbName(pTrans, pTopic->db, NULL);
+  mndTransSetDbName(pTrans, pTopic->name, NULL);
   code = mndTransCheckConflict(pMnode, pTrans);
   if (code != 0) {
     goto end;
diff --git a/source/dnode/mnode/impl/src/mndTrans.c b/source/dnode/mnode/impl/src/mndTrans.c
index 7ebaf6dda5..849b14255c 100644
--- a/source/dnode/mnode/impl/src/mndTrans.c
+++ b/source/dnode/mnode/impl/src/mndTrans.c
@@ -792,6 +792,22 @@ static bool mndCheckTransConflict(SMnode *pMnode, STrans *pNew) {
       }
     }
 
+    if (pNew->conflict == TRN_CONFLICT_TOPIC) {
+      if (pTrans->conflict == TRN_CONFLICT_GLOBAL) conflict = true;
+      if (pTrans->conflict == TRN_CONFLICT_TOPIC || pTrans->conflict == TRN_CONFLICT_TOPIC_INSIDE) {
+        if (strcasecmp(pNew->dbname, pTrans->dbname) == 0 ) conflict = true;
+      }
+    }
+    if (pNew->conflict == TRN_CONFLICT_TOPIC_INSIDE) {
+      if (pTrans->conflict == TRN_CONFLICT_GLOBAL) conflict = true;
+      if (pTrans->conflict == TRN_CONFLICT_TOPIC ) {
+        if (strcasecmp(pNew->dbname, pTrans->dbname) == 0 ) conflict = true;
+      }
+      if (pTrans->conflict == TRN_CONFLICT_TOPIC_INSIDE) {
+        if (strcasecmp(pNew->dbname, pTrans->dbname) == 0 && strcasecmp(pNew->stbname, pTrans->stbname) == 0) conflict = true;
+      }
+    }
+
     if (conflict) {
       mError("trans:%d, db:%s stb:%s type:%d, can't execute since conflict with trans:%d db:%s stb:%s type:%d",
              pNew->id, pNew->dbname, pNew->stbname, pNew->conflict, pTrans->id, pTrans->dbname, pTrans->stbname,
diff --git a/source/dnode/vnode/src/tq/tq.c b/source/dnode/vnode/src/tq/tq.c
index 815e9647b5..3396803f08 100644
--- a/source/dnode/vnode/src/tq/tq.c
+++ b/source/dnode/vnode/src/tq/tq.c
@@ -879,20 +879,7 @@ int32_t tqProcessSubscribeReq(STQ* pTq, int64_t sversion, char* msg, int32_t msg
     } else {
       tqInfo("vgId:%d switch consumer from Id:0x%" PRIx64 " to Id:0x%" PRIx64, req.vgId, pHandle->consumerId, req.newConsumerId);
       atomic_store_64(&pHandle->consumerId, req.newConsumerId);
-      //    atomic_add_fetch_32(&pHandle->epoch, 1);
-
-      // kill executing task
-      //    if(tqIsHandleExec(pHandle)) {
-      //      qTaskInfo_t pTaskInfo = pHandle->execHandle.task;
-      //      if (pTaskInfo != NULL) {
-      //        qKillTask(pTaskInfo, TSDB_CODE_SUCCESS);
-      //      }
-
-      //      if (pHandle->execHandle.subType == TOPIC_SUB_TYPE__COLUMN) {
-      //        qStreamCloseTsdbReader(pTaskInfo);
-      //      }
-      //    }
-      // remove if it has been register in the push manager, and return one empty block to consumer
+      atomic_store_32(&pHandle->epoch, 0);
       tqUnregisterPushHandle(pTq, pHandle);
       ret = tqMetaSaveHandle(pTq, req.subKey, pHandle);
     }