What happens when this goes wrong?
Every other page shows this payment working. Here you choose what breaks, and follow the damage — because a hold, a return or a missed cut-off is the system working as designed, and reading one calmly is the job.
Pick a failure above. Nothing here is invented — each one is a reason code this rail really uses, at the step where it really strikes.
One payer bank, one payee bank, and a single proxy lookup are shown; the FAST clearing batch, the MEPS+ netting cycle, and exact settlement timings are described in plain terms rather than to the minute. Every failure here is authored on Singapore PayNow (addressing overlay on FAST), with the sources that back it.