Keep the payment screen focused
A useful QR checkout puts the amount, scannable code, payment status, and order reference in predictable places. On a phone, offer an app handoff where supported; on a desktop, keep the QR large enough to scan from another device. Avoid surrounding the code with instructions that obscure the actual payee or amount.
Verify the payee in the UPI app
The customer's UPI app is where they approve a payment. Before entering a PIN, they should check the displayed receiver and amount there. The website cannot approve a UPI payment on the customer's behalf. A QR scan or app launch only begins the flow; it does not mean funds were received.
Handle waiting and expiry honestly
Leave the checkout in a waiting state while verification is pending. Show a clear next step if the request expires. If a customer says they paid but the order remains pending, use the order reference and the merchant's transaction record to investigate instead of asking the customer to pay again immediately.