Attachment download

Hi, how can I download attachments?

I get JSON details about attachment via
API attachments docs

I have tried URL links from ontent_src, content_src_medium, content_src_small but Amazon AWS the URL link doesn’t have authorisation on Amazon AWS or the authentification from FreeAgent with Bearer code doesn’t work:
Only one auth mechanism allowed; only the X-Amz-Algorithm query parameter, Signature query string parameter or the Authorization header should be specified