Hello @Guedes, Bruno,
Thank you for connecting offline to discuss regarding this issue.
As we discussed during the call, we have determined that the issue occurs because the application is not sending a subsequent request to the token endpoint to obtain an access token for API authorization using the OAuth 2.0 Authorization Code Grant Flow.
Based on the network trace logs, we confirmed that your application is sending a GET request to the authorization endpoint to retrieve a code in response to your redirect URI. However, after receiving the code, it is not being exchanged for an access token by sending a POST request to the token endpoint, including the code and client_ID parameters in the request.
For more details on the Authorization Code Flow, please refer to the following documentation: OAuth 2.0 Authorization Code Flow
I hope this information is helpful. Please feel free to reach out if you have any further questions.
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Thanks,
Raja Pothuraju.