Hi @sergiocascales ,
I don't have the answer unforunately (I came here for a solution and have exactly the same problem as you).
This is what I noticed:
- There is a website where you can try the PowerBI APIs
- It gives you a BEARER token (JWT)
- If you use a JWT decoder (https://jwt.io), the contents give a random app_id that doesn't appear to be part of my tenant, and scopes that I haven't granted (but seem necessary).
- Decoding the token based on your approach doesn't seem to have the correct scope information embedded.
From what I have read, you should be able to authenticate without username/password (as this requires MFA), but with the app_id & client_secret approach.
Hoping someone could link to a working guide (using Postman), or Microsoft documentation (in English please ;).