One to one chatroom problem

I want to open an one to one chatroom with a user who is not in the contact list.

here is the chatroom creation code:

ChatManager chatManager = SparkManager.getChatManager();

chatManager.activateChat(jid,“testing”);

The problem is:

When user B creates the chatroom with the user A for the first time, the chat progress is normal. IF A and B both close the chatroom, and B creates the chatroom again, A can receive the message from B , but B cannot receive message from A.

After that , i changed the code to:

ChatManager chatManager = SparkManager.getChatManager();
ChatRoom chatRoom = chatManager.createChatRoom( jid,nickname, “The Chat Title”);
ChatContainer chatContainer = chatManager.getChatContainer();

chatContainer.activateChatRoom(chatRoom);

The problem still exist.

May anyone help ?

Thanks a lot.