Embed API - Fetching JWT License Issue

I have set up credentials and correct domains for the Embed API. When I attempt to load a PDF I get:

Access to fetch at 'https://viewlicense.adobe.io/viewsdklicense/jwt' from origin *** has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

I tried with the pdf formatted as both a blob and a base64 string. The pdf flashes up and then disappears and I get the ubove error in dev tools. The origin for the request matches entered domain entered into the adobe console (other than the 'https://' which cannot be added)

I have also tried with entering wildcard subdomain, as well as just root domain, in the console, and my credential string is correct.

Please advise any ideas on resolution. Thanks.