Creating a media container with a caption in the payload returns the following error:

{ "error": { "message": "An unexpected error has occurred. Please retry your request later.", "type": "OAuthException", "is_transient": true, "code": 2, "fbtrace_id": "AAcBobi9u_ms6Sr2YYizC-J" } }

However, it works fine with an empty caption.

This issue is specific to the user.