Root Cause

• Test account used in production: The bank account provided is configured for test environments and cannot be used for live transactions.
• Incorrect environment configuration: The transaction was attempted using test credentials or accounts in a production environment.
• Saved test data used: Test bank account details were accidentally stored and used for live transactions.
• Gateway restrictions: The payment gateway prevents test accounts from being used outside sandbox environments.

Troubleshooting and Solutions

• Ask the customer to provide valid bank account details for live transactions.
• Verify that the correct environment (production) is being used for the transaction.
• Ensure that any saved test data is cleared from the customer's stored payment methods.
• Retry the transaction after updating with valid bank account information.
• Review payment gateway settings to prevent test accounts from being used in production environments.