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.
The exact UPI message set, the PSP / bank / third-party-app roles, and the precise deferred-net settlement cycle times are collapsed into single steps here. Every failure here is authored on India UPI — Unified Payments Interface, with the sources that back it.