Why is an Instagram direct message displaying 'Unsupported Attachment' in the Smart Inbox?

From the desk of Jade McKeown, Product Support Specialist

The message Unsupported Attachment refers to direct messages that contain Stickers, GIFs, Story reply GIFs, Audio and images that are sent back to back via Instagram direct message. This is due current limitations in the Instagram API. Read more about supported Instagram direct message types in the Smart Inbox here.