CyberSource::PayerAuthSetupRequest is not working, returns 400 constantly

Hi, I'm integrating Cybersource payments into our systems and am using this gem to call the api. In the front end I have flex microform that gives me a token and I don’t have control over card details.

When I try to setup payer authentication for 3DS payments I send MerchantID, key and secret alongside with client reference code and decoded jti token from flex token and always receive 400 with "reason\":\"INVALID_DATA\",\"message\":\"Declined - One or more fields in the request contains invalid data\".

I'm following this example https://github.com/CyberSource/cybersource-rest-samples-ruby/blob/master/Samples/PayerAuthentication/setup-completion-with-flex-transient-token.rb

It also happens on your live console https://developer.cybersource.com/api-reference-assets/index.html#payer-authentication_payer-authentication_setup-payer-auth_samplerequests-dropdown_setup-completion-with-flex-transient-token_liveconsole-tab-request-body so I wonder if there's a bug?

Thank you.

Start by comparing the request described in the issue with the linked Cybersource Ruby sample and live-console request for setup completion with a Flex transient token. Trace how the gem constructs and sends the payer-authentication request, using the reported INVALID_DATA response to identify the offending field. Done means the documented request succeeds without the persistent 400 response and the behavior is covered by an appropriate test.