"The user is not Authenticated" - Embed API

I am getting an error when using the AdobeDC Embed API where somthimes it fails to embed the PDF and I get an console error stating "The user is not authenticated". This happens intermittently, often when I refresh the page and try comming back to the same PDF.

The API key I am using does not change, so I am unsure what is causing it to fail authentication.

I have checked the cookies and I am not sure if there is a correlation. Sometimes there are no cookies when I get an error, sometimes there are cookies in an "adobe.com" directory and somethimes in a "documentcloud.adobe.com" directory.

I would appreciate any help.