I can't get my Cognito license

hello.

I'd like to get a secret key and access key ID as a cognito license.

cognitoUser.authenticateUser(authenticationDetails, {
      onSuccess: function (result) {
        const idToken = result.getIdToken().getJwtToken();

        AWS.config.credentials =
        new AWS.CognitoIdentityCredentials({
        IdentityPoolId:
          'ap-northeast-2:7fc9xxxx-xxxx-xxxx-xxxxx-xxxxx',
        Logins: {
          'cognito-idp.ap-northeast-2.amazonaws.com/userPoolid':
          idToken,
        },
    }) 
}

On the Cognito aws Identity Pool page, it is confirmed that the identity browser has become a credential.

However, in getCredentials, "Could not load credentials from CognitoIdentityCredentials" is generated.

AWS.config.getCredentials(function (err) {
	if (err) return console.error(err.stack);
  else console.log('Access key:', AWS.config.credentials.accessKeyId);
})

If you look at the AWS.config.credentials console log, there are no values other than the parameters you put in.

Problem not found.

Is it right to get the secret key issued through Cognito Identity Credentials?