We assign the Declined Card symptom to an issue if it matches these matching parameters:
^40[04]-.carts./payment-information$
^40[04]-payments.bigcommerce.com/.*/orders/payments$
Unfortunately, the way Salesforce throws their declined credit cards does not surface them with the usual 400 level error. Because of this anomaly, Noibu has no way to capture this issue in the platform.
If you have any questions or would like help working around this issue, please reach out your CSM or contact us at support@noibu.com.