Start with a reviewed case
Link the proposed supplier query to the exact agreement and invoice rows and the calculation. Have a person approve the wording before sending it through their own channel. Keep an unsent draft labeled unsent.
Record what the supplier actually said
Capture the reply date, channel, reference and amount the supplier promised. If the response is ambiguous, record that uncertainty. A promised USD 54.00 remains pending USD 54.00 and verified USD 0.00 until later evidence appears.
Check the next source document
On a later invoice or credit note, find a line that identifies the same supplier adjustment. Match its currency and reference, and preserve the document fingerprint plus row or page. A line with an uncertain connection stays in review.
Close only the evidenced portion
When a later credit line proves USD 20.00 against that USD 54.00 case, verified becomes USD 20.00 and USD 34.00 remains outstanding. The promise and later credit stay as separate dated events.
A generated draft, sent request, supplier promise and applied credit are four different facts. Keep each one labeled so a report cannot overstate recovery.
Follow the fictional timeline