ConnectIQ IOS SDK, Delegate issue(registerForAppMessages).

Hello,

After unregister app for messages When i try to register again a listener for ConnectIQ message from an app it is not start working. 
If you  register a listener for ConnectIQ message from an app First time it is working fine. But if you will unregister it then try to register again it will not work.

My code.

Register application for App messages.

ConnectIQ.sharedInstance().register(forAppMessages: app, delegate: self)

Unregister application for app messages

ConnectIQ.sharedInstance().unregister(forAllAppMessages: self)

Delegate Name:- IQAppMessageDelegate

Method name:- func receivedMessage(_ message: Any!, from app: IQApp!).