Three duplicate-payment cases that need different answers

Four duplicate types

Safe check

1. Compare original documents, not thumbnails.
2. Compare bank account and immutable bank references.
3. Check booking and value dates.
4. Look for reversal or refund.
5. Confirm recurring frequency and business facts.
6. Check whether either row already settles an invoice.
7. Route the evidenced correction.

Do not delete a bank source merely because another row looks similar. Corrections should preserve what was received and why the accounting changed.

Three cases that look similar but end differently

Pending and final card row

A €79.00 authorization appears on Monday, the final €79.00 charge on Wednesday, and the authorization reverses on Thursday. One payment and one expense remain. DeinHans can keep the candidates together while status and reversal evidence are checked.

The same statement imported twice

Two rows share the same bank account, source reference, amount, date and statement provenance because June was imported twice. This is one external event and two internal copies. The approved duplicate resolution preserves the import history; it does not pretend the bank sent only one file.

Two genuine supplier payments

Two booked €540.00 debits have different bank references and no reversal. Both cash movements remain. The owner confirms whether the supplier was paid twice; the invoice must not be used to close both. Any refund request and later refund become separate evidence.

DeinHans can surface duplicate, transfer and reversal candidates from source evidence without publishing detection logic or thresholds. The owner confirms the business event; the accountant approves any accounting correction.

Roles

The owner confirms whether two purchases happened. Software compares sources and flags conflicts. The accountant reviews any entry reversal, refund, or open-item effect.

DeinHans can keep suspected duplicates in review rather than hiding one. A duplicate check is complete only when the source and cash history explain the result.

Prevention

Validate statement coverage before import, retain source identifiers, separate pending from booked card activity, compare recurring suppliers with contract frequency, and review duplicate warnings before close.

Correction paths are not interchangeable

If the same source row was imported twice, preserve the import evidence and neutralize the internal duplicate through the approved process. If two genuine bank payments occurred, both cash movements remain; the business may need a supplier refund or an open receivable. If one invoice was booked twice but paid once, correct the duplicate accounting record without deleting the single bank event. State which case applies before acting.

Validate after correction

Re-run bank reconciliation, supplier open items, expense totals and affected VAT or period review. Confirm that the surviving item retains original document and bank reference. Record who approved the correction, why the other candidate was not a separate event and whether a report or export must be regenerated.

For subscriptions, compare service period and invoice number, not only the amount. For split shipments or instalments, confirm that similar charges correspond to separate documents. A good duplicate control is deliberately cautious because deleting a real event can be harder to detect than leaving a candidate in review.

Close the case with evidence

Use one of a small set of outcomes: not a duplicate, duplicate import, duplicate document, genuine double payment, temporary authorization, or unresolved. Record the decisive reference and next action. For a genuine double payment, track refund request and later receipt separately; the case is not finished merely because the accounting entry was reversed.

At close, compare unresolved candidates with the bank statement and open-item lists and assign an owner and date. Report both candidate count and cash amount: many harmless authorization pairs and one material double payment require different attention. Recheck any unresolved item before carrying it into the next period.