mister--wizard on Nostr: that makes sense, since later similar attempts with different counterparty resulted ...

that makes sense, since later similar attempts with different counterparty resulted in hung transaction (no timeout. no notice of successful payment. i eventually hit cancel.), which i took to mean invoice had already been paid by someone else. so looks like invoices are single-use. not following balance to know whether payment/balance reverse, but at least 30 min or so following transaction, my recollection is that was still in history. therefore looks like app debits/credit transaction amount from balance despite failed payment but would need to test more carefully to confirm.