Start with the evidence
Open the final export and compare its recipient, reference, dates, currency and totals with the supporting agreement. Check that no last-minute edit reintroduced an old address, description or amount.
Work through the example
A reviewer approved draft 03, but export 02 is still in the attachment folder. Matching the version label and visible total helps catch the error before an otherwise polished document reaches the customer.
Make the next step clear
Keep the approved version and the release note together. A clear filename helps, but the content itself must match. Record unresolved questions explicitly and keep the document in draft when they affect what the recipient should receive.
Keep the source context
Treat an invoice draft as a description of an agreed business event. Keep the source agreement nearby and distinguish document preparation from approval, sending and receiving payment. These are separate steps even when they happen close together.