Hi @alexandru.dan,
Thanks for reaching out to the Auth0 Community!
I understand that you have questions about getting an access token for validation.
From what I can tell, it seems that you have obtained an opaque access token, which cannot be decoded with jwt.io. In this case, you can directly use that opaque access token to call the /userinfo
endpoint. See the Opaque Access Tokens documentation to learn more.
Let me add that the audience
parameter must be specified to get an access token in the JWT format.
I hope this helps!
Please reach out if you have any additional questions.
Thank you.