Define the service and the acceptance event.
Name the seller, customer, user, service category, deliverable or entitlement, cancellation, support, and who approves the commercial and specialist conclusions.
Separate VND display from settlement.
Document displayed amount, quotation, contract currency, provider charge, settlement, refund, accounting, rounding, timestamp, and exchange-rate ownership. The interface must not imply these are identical.
Use the actual client account.
Verify entity, bank, customer, service, currency, identity, location, and provider policy. Faith Forge Labs does not supply a substitute merchant route or guarantee account approval.
Make unfinished money visible.
Model pending, failed, expired, duplicated, disputed, reversed, refunded, and partially fulfilled states. Keep honest user messages, safe retries, provider identifiers, and an operator exception queue.
Connect the transaction to its record.
The approved invoice, receipt, tax evidence, order, entitlement, refund, fulfilment, and accounting handoff need compatible identifiers and a named owner when records disagree.
Official banking and tax sources inform the board.
The State Bank of Vietnam and the Tax Department are official starting points. Qualified Vietnamese and US advisers determine applicable tax, invoice, payment, licensing, and commercial treatment. Faith Forge Labs implements their approved system behavior and checks the real route.