AD Connector One LDAP Modify failed transaction makes all subsequent transaction failed ...

Refer to few thousand of repeating error in the log\

20180803,05:38:08,UNIFY Identity Broker,Connector,Warning,"Update entities to connector failed.
Update entities [Count:3215] to connector AD Users failed with reason Received error code EntryAlreadyExists for item with dn CN=redacted,DC=au. Message: 00002071: UpdErr: DSID-031B0B87, problem 6005 (ENTRY_EXISTS), data 0
. Duration: 00:00:09.5226690
Error details:
System.Exception: Received error code EntryAlreadyExists for item with dn CN=redacted,DC=au. Message: 00002071: UpdErr: DSID-031B0B87, problem 6005 (ENTRY_EXISTS), data 0
 ---> System.DirectoryServices.Protocols.DirectoryOperationException: The object exists.
Server stack trace: 
   at System.DirectoryServices.Protocols.LdapConnection.ConstructResponse(Int32 messageId, LdapOperation operation, ResultAll resultType, TimeSpan requestTimeOut, Boolean exceptionOnTimeOut)
   at System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage(IntPtr md, Object[] args, Object server, Object[]& outArgs)
   at System.Runtime.Remoting.Messaging.StackBuilderSink.AsyncProcessMessage(IMessage msg, IMessageSink replySink)
Exception rethrown at [0]: 
   at System.DirectoryServices.Protocols.LdapConnection.EndSendRequest(IAsyncResult asyncResult)
   at System.Threading.Tasks.TaskFactory`1.FromAsyncCoreLogic(IAsyncResult iar, Func`2 endFunction, Action`1 endAction, Task`1 promise, Boolean requiresSynchronization)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at Unify.Connectors.AD.ADAgent.<ErrorCheckRequest>d__24`1.MoveNext()
   --- End of inner exception stack trace ---
   at Unify.Framework.Auditing.AuditingExtensions.<>c__DisplayClass4_0.<TaskContinueWithExceptionPassthough>b__0(Task t)
   at System.Threading.Tasks.Task.Execute()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Unify.Product.IdentityBroker.EventNotifierUpdatingAsyncConnectorDecorator.<UpdateEntitiesAsync>d__3.MoveNext()",Normal
20180803,05:38:08,UNIFY Identity Broker,EntitySaver,Error,"The entity 546564 (e5b5ef1a-46df-4751-9878-e3a8e8fff5c8) for the adapter AD User Adapter (9f73e5e5-30df-4142-b850-db3e31f0a931) failed to update for the following reasons: Received error code EntryAlreadyExists for item with dn CN=redacted,DC=au. Message: 00002071: UpdErr: DSID-031B0B87, problem 6005 (ENTRY_EXISTS), data 0
",Normal
20180803,05:38:08,UNIFY Identity Broker,EntitySaver,Error,"The entity 603085 (b108073b-e6f1-4ffb-8d9b-02c23f7c1efa) for the adapter AD User Adapter (9f73e5e5-30df-4142-b850-db3e31f0a931) failed to update for the following reasons: Received error code EntryAlreadyExists for item with dn CN=redacted,DC=au. Message: 00002071: UpdErr: DSID-031B0B87, problem 6005 (ENTRY_EXISTS), data 0
",Normal