From what I understood from your words, you’re asking about the reason for using a one-time QR code, Lightning, that can only be paid once. For example, you can configure one-time payments in the Wallet of Satoshi. You put in 10 reais, 10 dollars, and that payment can only be made once, say, 10 dollars. That’s what I understood. And what I think is that there are NGOs that do this. Since they’re not actually for profit and just want to help people, they set a fixed amount. But I prefer to use it normally. You just put your key, your email, and receive as usual, whatever the maximum, minimum, or any amount