I'm happy to help you with this issue. At this time, the only way to query the CyberSource Payments sandbox is by creating a merchant account directly with CyberSource. Here's the link - https://developer.cybersource.com
The CyberSource site gives users a simple way to test their account credentials:
Additionally, here are the following links for sample code: https://github.com/CyberSource/cybersource-rest-samples-java/blob/master/src/main/java/samples/payme...
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