Download Gmail attachment from octet-stream

does anyone know how to download Gmail Attachment, which is presented as “octet-stream” from mail message? It’s not seen as regular attachment in mail message. How do I save this one?
Here I’m attaching part of the original message:

Content-Type: application/octet-stream; name=“testFile-07112022 023819.xlsx”
Content-Transfer-Encoding: base64
Content-Disposition: inline; filename=“testFile-07112022 023819.xlsx”

Or anyone does know how to forward gmail message in Studio using GSuite? I’m not able to use any other package, as I’m authenticating through Service Account.