The payment screen listed invoices and said nothing about an open advance, so it would pay the full amount while the vendor kept the advance and the cash both.
Open Vendor Credit Is Named Before the Payment Goes Out
One vendor held a ₹5,00,000 approved advance with nothing allocated, and two open invoices. The manual payment screen showed the invoices and had no concept of a credit at all.
Open credit is now reported on the screen, in two tiers split on currency. A credit in the same currency as a selected invoice could have cleared it, so it is named and totalled and the payment waits on a written acknowledgement — a tick box reading “pay without applying ₹X of open credit”. A credit in any other currency could not have been applied to this payment anyway; it is reported and blocks nothing, because asking for a confirmation on a payment that was never at risk is how confirmations become reflexive.
The rule lives in the endpoint, not only on the screen. It is deliberately soft: an advance is not proof that it belongs to the invoices being paid, and a hard refusal would strand an operator who has no right to apply the credit either. A bypass is stamped on the payment’s own notes naming each credit left unapplied — and nothing is stamped when the box was ticked but no credit was actually open, because that would be a false statement on the document.