Payment Gateway Questions & Answers

Insert the UPI transaction ID from the reconciliation ledger into the e-invoice PDF’s payment section as a fixed, non-editable field.

Place it near the “Payment Reference” block so auditors can trace it back to the GeM transaction.

Include the purpose code/MCC only if needed for GeM or internal audits, not GST validation.

Lock the field after PDF generation to preserve audit integrity.

Include the UPI transaction ID as a dedicated, fixed field in the e-invoice payment section (label it UPI Ref / Transaction ID) pulled directly from the ledger entry tied to that down-payment.

Render it next to Payment Reference and also store the parent/child UPI links (if split payments) so auditors can trace the full chain

Make the field immutable once the PDF is generated and include the purpose code/MCC only when required for internal/GST audits.

Log the export event (timestamp, invoice id, ledger reference, exported value) in your audit trail for traceability.

Recommend NetBanking (IMPS/RTGS/NEFT) as the primary fallback for high-value vehicle down payments.

Offer debit/credit cards only if the dealership supports large-ticket card processing.

Enable split UPI only if dealership and PSP policies permit it.\

Show a clear UPI limit reached, choose another payment method prompt to prevent checkout failures.

Map each down payment to the correct automotive/vehicle MCC or purpose code based on the product (car, bike, commercial vehicle).

Embed this purpose code in the UPI collect/deep-link payload so it reaches the gateway for audit trails.

Store the purpose code + UPI txn ID in the POS ledger for reconciliation.

Block UPI initiation if a vehicle transaction lacks a mapped purpose code.

• Require idempotency keys + retry cap: attach an idempotency key per down-payment, retry only transient errors (5xx/timeouts), max 3 retries per transaction.
• Use exponential backoff with jitter + circuit breaker: base 500ms, factor×2, max 8s, jitter; open circuit after ~5 failures for 60s to stop hammering the PSP.
• Enforce concurrency limits per merchant and globally and push retries to delayed queue with TTL (e.g., 15 minutes) that maintains order and links attempts to original txn Add fallbacks & observability: route to NetBanking/card if retries are exhausted, log idempotency outcomes, emit metrics for retry count, latency, and circuit state, and alert ops when thresholds are hit.

Add a pre-payment cap check that detects when a vehicle down payment exceeds the ₹5L UPI per-transaction limit.

Trigger an auto-split workflow that divides the amount into compliant child payments while preserving the automotive purpose code/MCC.

Generate linked child UPI requests with separate txn IDs and route each through the PSP with full idempotency.

Reconcile all splits back to the original order so settlement, refunds, and audits stay consistent. 

Add a pre-payment cap check that detects when a GeM UPI amount exceeds the ₹5L per-transaction limit.

Trigger an auto-split workflow that breaks the total into compliant child amounts while preserving the GeM purpose code/MCC.

Generate linked child UPI requests with separate txn IDs and route each through the PSP.

Reconcile all splits back to the original PO/invoice so settlement, refunds, and audits stay consistent.

Test full, partial, and split refunds to ensure each maps back to the correct parent/child UPI txn IDs and preserves the GeM purpose code.

Simulate PSP/bank outcomes (success, failure, partial) and verify ledger reversals, GST adjustments, and PO linkage.

Run chargeback scenarios to confirm dispute evidence ties to the original txn chain.

Validate reconciliation so refunded amounts match UPI settlement reports without breaching NPCI caps.

Check the down payment’s MCC/purpose code = automotive and confirm the dealer is NPCI-verified for high-value UPI.

Validate the payable amount against the ₹5L per-txn and ₹10L daily caps before displaying eligibility.

Use the gateway/PSP pre-auth response to confirm high-limit acceptance.

Show a higher-limit eligible banner only after all checks pass and log the result for audit.

Enable a daily aggregate cap alert when vehicle down-payment UPI receipts approach the ₹10L per-day limit.

Add a high-value instalment alert for payments nearing the ₹5L per-txn cap.\

Use an unmapped-purpose alert to catch transactions missing the automotive purpose code/MCC.

Enable a settlement mismatch alert when UPI receipts don’t reconcile with down-payment invoices or ledger postings.