In the last 3 hours, my system cannot send image attachment to Facebook Messenger API. I've got this error response with subcode "2018047".

{
  "error": {
    "message": "(#100) อัพโหลดไฟล์แนบไม่สำเร็จ",
    "type": "OAuthException",
    "code": 100,
    "error_subcode": 2018047,
    "fbtrace_id": "ARf0A2vLG4TIptN9Rx2kX4K"
  }
}

Many online resources suggested that this subcode implies unmatched image type between file extension and image itself, but it is not the case for me. My system has been working normally without issues until recently.

Other attachment type such as videos, PDFs or Excel files can be send as usual.

The attached screenshot shows that this error code occurs only a few hours ago.