Twenty-one exceptions, as operations sees them. Read the symptom, pick the first investigation action you would take, and learn immediately whether it is right, what evidence it produces, and what happens next. Work through all 21 and see your score for correct first try investigations. Each scenario carries a timestamped message trail (MsgId, UETR, EndToEndId, status code) where one exists, because an investigation is proved by its audit trail, not by prose alone.
Score: 0 correct first try out of 0 investigated (21 scenarios)
1. Insufficient funds
What operations sees. A pacs.002 arrives with reason code AM04. The customer account held USD 8,000, but the payment was USD 25,000. The customer calls to ask where the money is.
What is your first investigation action?
2. Invalid account
What operations sees. A pacs.002 arrives with reason code AC01. The beneficiary account number fails the modulus check at the beneficiary bank. The payment never reached the beneficiary.
What is your first investigation action?
3. Invalid BIC
What operations sees. The payment is held at validation. The beneficiary bank BIC in the instruction is not a live BIC in the directory, so routing cannot resolve the next hop.
What is your first investigation action?
4. Invalid IBAN
What operations sees. Validation rejects the instruction. The beneficiary IBAN fails the modulus 97 check, so the account number cannot be real as written.
What is your first investigation action?
5. Invalid XML
What operations sees. The receiving bank rejects a pacs.008 at its gateway. The message fails schema validation: a mandatory element is missing and a date is in the wrong format.
What is your first investigation action?
6. Missing mandatory info
What operations sees. A payment is held before screening. The debtor address is missing, and the receiving bank requires complete debtor data before it will accept the payment.
What is your first investigation action?
7. Duplicate payment
What operations sees. Reconciliation shows two USD 12,500 debits with the same reference INV-9100 against one customer instruction. The beneficiary may have been paid twice. Trail: pacs.008 MsgId PACS008-20261106-007, InstrId INSTR-20261106-007, EndToEndId INV-9100, UETR a3e1f2b4-5c6d-4a7e-9b1c-2d3e4f5a6b7c, 2026-11-06 09:05; second debit with the same EndToEndId at 09:41.
What is your first investigation action?
8. Sanctions hit
What operations sees. Screening holds a USD 200,000 payment. The beneficiary name is a close fuzzy match to a name on a sanctions list. The payment cannot proceed until the match is cleared or confirmed.
What is your first investigation action?
9. Fraud alert
What operations sees. The fraud engine scores a GBP 90,000 payment as high risk. The payee is new, the amount is ten times the customer normal payment, and the device is unrecognised.
What is your first investigation action?
10. FX failure
What operations sees. A USD 100,000 payment to Tokyo needs conversion to JPY, but the FX rate service returns no rate for the value date, so the payment cannot be priced or executed.
What is your first investigation action?
11. Correspondent unavailable
What operations sees. The correspondent bank in New York does not acknowledge the pacs.008 within the expected time. Its system is down, and the payment status is unknown. Trail: pacs.008 MsgId PACS008-20261105-001, EndToEndId INV-8841, UETR a3e1f2b4-5c6d-4a7e-9b1c-2d3e4f5a6b7c, sent 2026-11-05 09:05; no pacs.002 received by 09:35.
What is your first investigation action?
12. Clearing timeout
What operations sees. A Faster Payments single immediate payment was submitted but no acknowledgement arrived within the timeout window. The clearing system may be slow, or the message may be lost. Trail: submission reference FPS-20261106-7781, EndToEndId INV-9080, sent 10:02; no acknowledgement by 10:03.
What is your first investigation action?
13. Settlement failure
What operations sees. The RTGS settlement account (CHAPS/T2) has insufficient funds at the central bank cut-off. A batch of payments cleared but cannot settle, and the value date is at risk. Trail: RTGS queue report 16:40, value date 2026-11-06; payments queued since 15:55.
What is your first investigation action?
14. Rejection
What operations sees. A pacs.002 arrives rejecting a EUR 25,000 payment with reason code AC04, closed account. The beneficiary account was closed last month.
What is your first investigation action?
15. Return
What operations sees. A pacs.004 arrives returning USD 85,000 less a USD 20 intermediary fee, so USD 84,980 comes back. Reason code AC04, closed account. This is a different payment from INV-8841: reference INV-9021, original USD 85,000, charge bearer SHAR. Trail: original pacs.008 MsgId PACS008-20261106-004, EndToEndId INV-9021, 2026-11-06; pacs.004 MsgId PACS004-20261107-003, 2026-11-07 09:30.
What is your first investigation action?
16. Reconciliation mismatch
What operations sees. The nostro statement shows a USD 75,000 debit, but the internal ledger shows USD 75,015 for the same reference. A USD 15 correspondent fee was deducted and not recorded.
What is your first investigation action?
17. Missing/delayed confirmation
What operations sees. A USD 120,000 payment was sent three days ago. No pacs.002 acknowledgement, no settlement confirmation, and no return has arrived. The customer asks if the supplier was paid. Trail: pacs.008 MsgId PACS008-20261103-002, EndToEndId INV-8802, UETR a3e1f2b4-5c6d-4a7e-9b1c-2d3e4f5a6b7c, sent 2026-11-03 11:20; no pacs.002, no pacs.004, no camt.029 since.
What is your first investigation action?
18. Recall request (camt.056)
What operations sees. A customer realises a USD 12,500 payment (INV-9100) was sent twice and asks for the duplicate back. The beneficiary account has already been credited. Trail: original pacs.008 MsgId PACS008-20261106-007, EndToEndId INV-9100, settled 2026-11-06; camt.056 not yet sent.
What is your first investigation action?
19. Customer cancellation before settlement
What operations sees. A customer calls an hour after instructing a USD 25,000 payment (INV-8841) and asks to cancel it. The payment has been accepted (ACCP) but has not yet settled (no ACSC). Trail: pacs.008 MsgId PACS008-20261105-001, EndToEndId INV-8841, UETR a3e1f2b4-5c6d-4a7e-9b1c-2d3e4f5a6b7c, status ACCP at 09:20, no settlement confirmation yet.
What is your first investigation action?
20. Clearing rejection
What operations sees. Clearing rejects a EUR 25,000 SEPA payment with a pacs.002 RJCT, reason code AM05 (duplicate payment): the clearing house already holds a payment with the same MsgId. Trail: pacs.008 MsgId PACS008-20261106-011, EndToEndId INV-9090, sent 08:15; pacs.002 RJCT AM05 at 08:17.
What is your first investigation action?
21. Routing failure
What operations sees. A USD 40,000 payment to a new destination country cannot be routed: no correspondent route exists in the routing table, and the intermediary bank that would carry it has rejected the route. Trail: instruction INV-9110, value date 2026-11-07; routing engine returned 'no route' at 14:20.
Reject (pacs.002 RJCT): before settlement. Nothing settled, the customer is re-credited in full. Return (pacs.004): after settlement, when the creditor agent cannot credit (for example AC04 closed account). Only the creditor agent sends it. Recall / cancellation request (camt.056): the debtor agent asks for funds back, before settlement or after credit; the answer is a pacs.004 with reason FOCR (positive) or a camt.029 (negative). Reversal: a distinct R-transaction, for example pacs.007 for a SEPA direct debit reversal, or an automatic scheme reversal on a Faster Payments timeout. Repair: the same payment with corrected data, re-released as a new instruction with a fresh InstrId and the same EndToEndId. Retry: resending the same message with the same MsgId and UETR, only after proving the original was not received. Investigation: a pacs.028 status request (answered by pacs.002) when a payment already sent has no confirmation; for SCT Inst it is sent if no response arrives after 25 seconds.