System account - client_credentials grant were invalid

[Dhanya joy]

I used the system account to request the token from Cerner sandbox and it was successful. But when I try the same request against non-prod, I am getting error 

https://authorization.../tenants/.../protocols/oauth2/profiles/smart-v1/token?grant_type=client_credentials&scope=system%2FPatient.read

Cerner-Correlation-ID- 69625e7e-e6f5-4b74-8013-abfcc62ce1db 

Account ID : fab540b3-7422-44b1-b851-aef83a03ee6a

 I was told that my app is whitelisted under non prod env.

Error uri says:

Information to provide to Unknown Application

The credentials used in the client_credentials grant were invalid.  

What am I doing wrong here?

[Aaron McGinn (Cerner)]

To authorize against a client non-production domain, you will need to use a system account in the SandboxCernerCentral portal [1]. Note that you will also need to have that app within the v1 developer portal [2].

[1] https://sandboxcernercentral.com/system-accounts/

[2] https://code.cerner.com/v1/developer/smart-on-fhir/apps

-Aaron (Cerner)

[Dhanya joy]

Thanks that explains why the error