3706858 - authentication error 401 while using IAS API with Bearer Token

• An error occurs while attempting to use the API with Identity Authentication Service (IAS) tenant to extract real-time user data (e.g., number of users, active users, inactive users).
• Error message: "Authentication credentials are invalid or not allowed for this endpoint."
• Encounter a 401 error with the message: "Authentication credentials are invalid or not allowed for this endpoint."
  
  {
    "schemas": [
      "urn:ietf:params:scim:api:messages:2.0:Error"
    ],
    "status": "401",
    "detail": "Authentication credentials are invalid or not allowed for this endpoint."
  }

Identity Authentication Service

authentication error, 401 error, IAS API, Identity Authentication Service, Bearer Token, client secret, client credentials, grant type, API endpoint, Postman, Manage Users role, system administrator, application/json , KBA , BC-IAM-IDS , Identity Authentication Service , BC-IAM-OID , OIDC/OAUTH2 component in SAP Cloud Identity Services , Problem