When you generate an invoice for a product or service with OpenNode, your customer may accidentally underpay the invoice. This can occur if the payee doesn't include a few extra sats to cover the network fees for an on-chain Bitcoin transaction.
If an invoice is underpaid, the customer will be shown another invoice for the remaining balance. They will have the option to make an additional payment to complete the transaction or request a refund for the impartial amount already paid.
OpenNode offers an underpaid threshold feature that allows you to set a limit on what you are willing or not willing to accept for an underpaid invoice. Learn more about our underpaid threshold feature here.