When using Cybersource you might encounter the above error, or a similar variation.
This error indicates that there's an error with the request being sent, but Cybersource don't generally provide a lot of details on which fields/values are causing the issues.
The first step when you encounter this error is to contact Cybersource to get a detailed explanation of which fields/values are causing trouble, and include this information when you contact firstname.lastname@example.org
Below you see an example of this error being displayed. Included in the pop-up is the "Request Id" which you'll need to reference when contacting Cybersource for details.