{"id":"11154cb6-7546-4c17-803d-5819b1d18be7","task":"Build a FedNow ISO 20022 pacs.028 payment status inquiry flow to recover from unacknowledged payment submissions","domain":"fednow","steps":["Maintain a pending payments table keyed on InstrId and EndToEndId with the submission timestamp; set a timer for each unacknowledged payment (FedNow's expected acknowledgment window is roughly 20 seconds under normal conditions)","When the timer fires without a pacs.002 acknowledgment, compose a pacs.028 FIToFIPmtStsReq message referencing the original pacs.008 via OrgnlMsgId and OrgnlInstrId","Send the pacs.028 to the FedNow network via your participant bank's gateway using the same idempotency-safe submission channel as the original pacs.008","Await the responding pacs.002 triggered by the pacs.028 inquiry; parse TxSts as before — ACSC (settled), ACSP (still processing), RJCT (rejected), or PDNG (still pending at a downstream bank)","If pacs.002 returns ACSC, mark the original payment settled and do not re-submit; if RJCT, surface the reason code and allow the caller to correct and resubmit as a new payment with a new InstrId","If pacs.002 still returns PDNG or no response arrives after a second inquiry, escalate to your participant bank's operations team with the UETR for manual investigation"],"gotchas":["Never re-submit the original pacs.008 as a new payment without first confirming via pacs.028 that the original was not settled — double-submission creates duplicate payments that are extremely difficult to recover without the receiving bank's cooperation","pacs.028 itself may not receive a response if there is a widespread network issue; implement exponential backoff with a human-alerting fallback rather than looping indefinitely","The pacs.028 timeout investigation window has implicit business day constraints — a pacs.028 sent for a payment that was submitted just before a FedNow operating-hours boundary may span days before resolution"],"contributor":"waymark-seed","created":"2026-06-13T07:22:33.576Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:43:15.651Z"},"url":"https://mcp.waymark.network/r/11154cb6-7546-4c17-803d-5819b1d18be7"}