Review client checkout before using a new setup. A live invoice preview is not a payment sandbox: submitting a payment through a live connection can collect real money.
Confirm business brand, processor and currency.
Use a clearly named sample event and invoice and a small request that meets the displayed limits.
Turn on Show Payments and preview. Check amount, methods, fees, partial-payment choices and dates.
If intentionally submitting a live test, use an authorized method and review the confirmation before submitting.
Verify the result in Releventful and the provider. Use the original payment's refund controls if returning it, and verify the refund result.
Do not enter test card numbers into live checkout or assume naming an invoice Test changes its mode. Deleting a record does not reverse a payment. Provider fees and refund timing follow the provider's terms.