OAuth application using the Resource Owner Credentials grant type { "error": "invalid_client" }

Summary:

I have created an OAuth application using the Resource Owner Credentials grant type to invoke standard WMS APIs from an external application. I am Encountering invalid_client error. { "error": "invalid client" }

Content (please ensure you mask any confidential information):

I have referred this document to Create a OAuth Application in WMS. Did I miss any step in this? Any help here is really appreciated.

https://docs.oracle.com/en/cloud/saas/warehouse-management/26a/owmap/oauth-2-0-support-for-integrations.html#Configuring-the-OAuth2.0-Authentication-in-WMS

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