Workfront Proj API reponds Authentication Exception: Authentication Exception: {0}

[JorgeHe9]

I need help calling the Workfront Proj (Project) API V21.0. I'm working on my Sandbox (sb01). When I do the call in Postman, I get the following authentication error:

"error": {

        "class": "com.attask.common.AuthenticationException",

        "message": "Authentication Exception: Authentication Exception: {0}"

    }

~~~Notes: 

• {{xxxx}} is obfuscating the actual value for security reasons
• My URL to connect to Workfront is: https://experience.adobe.com/#/@{{zyx}}/so:{{domain}}-Sandbox1/workfront/setup/oauth2-apps
• My workfront instance is https://{{domain}}.sb01.workfront.com

GET https://{{tenant}}.workfront.adobe.com/attask/api/v21.0/proj/search?status=CUR

Request Headers:

Accept: application/json

X-Requested-With: XMLHttpRequest

Authorization: Bearer XXXXXXXXXXXXXXXXXXXXX

User-Agent: PostmanRuntime/7.49.1

Postman-Token: 5c2d3fdc-d08d-4b5f-96c4-81bb8c4a3e16

Host: {{domain}}.sb01.workfront.adobe.com

Accept-Encoding: gzip, deflate, br

Connection: keep-alive

I got the Bearer token by calling:

POST https://{{tenant}}.workfront.adobe.com/integrations/oauth2/api/v1/jwt/exchange

Request Headers

Content-Type: application/x-www-form-urlencoded

User-Agent: PostmanRuntime/7.49.1

Accept: */*

Postman-Token: d62bb7bc-7508-4166-b389-f7bab19c0933

Host: tristategt.sb01.workfront.adobe.com

Accept-Encoding: gzip, deflate, br

Connection: keep-alive

Content-Length: 804

• ▶Request Body
  1.  client_id: "{{OAuth 2 Application ID -Machine to Machine-}}"
  2.  client_secret: "{{ClientSecret}}"
  3.  jwt_token: "{{Encoded Token-See below My JWT token}}"
  4.  grant_type: "urn:ietf:params:oauth:grant-type:jwt-bearer"

Using jwt.io to decode My JWT, it shows:

Decoded Header

{
"alg": "RS256",
"typ": "JWT"
}

Decoded Payload

{
"iss": "{{CustomerId}}",
"sub": "{{UserID}}",
"aud": "https://{{tenant}}.sb01.workfront.com",
"exp": 1764880489,
"iat": 1764879889,
"jti": "jwt-1764879889"
}

Any pointers is more than welcome!

[SuryaLakhani]

Hi @JorgeHe9 ,

I'd check if the call works with a user API key in Sandbox. You can get/generate one here:
/setup/customer-info

If that works, check the profiles you have added in the credential associated with your project in the console. Make sure SB01 is selected for the credential you are using.