I tried to follow the document to develop the customer feedback template. After I send JSON data using Graph API, I got an error "Attachment Unavailable" message on my end. I don't know is it a bug or something was wrong on my developer account because a few days ago it's working as expected. Thank you in advance.

Ref document: https://developers.facebook.com/docs/messenger-platform/send-messages/templates/customer-feedback-template/