MSMessagesAppViewController didStartSending overridden method is not called on SEND button tap

I have created an iMessage app to send MSSticker converting from images.

I have implemented following overridden method:  

override func didStartSending(_ message: MSMessage, conversation: MSConversation) {
        // Called when the user taps the send button.

    // Here I am adding rewards points on every sticker sending
    }

In iOS 10.2.0 it worked fine means rewards points get added but after updating to 10.2.1 is suddenly stopped and now I am no longer get callback to didStartSending method nor didCancelSending is called.

Is this a iOS 10.2.1 bug or should I do with any of the app settings for getting notified with the above method?

Any help would be greatly appreciated.

from MSMessagesAppViewController didStartSending overridden method is not called on SEND button tap