An invoice is unique, so no: once paid, you cannot pay an invoice again.
Your phone should be online to receive payments, I have received payment while the app was running in the background, but never tried with the app off.
Maybe give it a try yourself. You can put money into a web wallet like coinos and coinos.io and then try to send it back after swiping away the app or whatever you want to try.
Another wallet is Zeus. They offer a lightning address which is something you can give to multiple people and they can pay as many times as they like and as much as they'd like.
They also support always running in the background mode although it could drain your battery quicker.
Finally they also support a semi-trusted offline payment solution. For this, you should open the app at least once a day to make sure payments are settled properly, and there is a fee involved for the service for each payment.
Big Barry Bitcoin
npub1pkt…pxa6
2024-02-11 19:46:55
in reply to nevent1q…lcwf
Author Public Key
npub1pktmatjk0l8vn3jhfuwxaasjd65kn4ye9sce3egup7k993f8fg2q5tpxa6Published at
2024-02-11 19:46:55Event JSON
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"pubkey": "0d97beae567fcec9c6574f1c6ef6126ea969d4992c3198e51c0fac52c5274a14",
"created_at": 1707677215,
"kind": 1,
"tags": [
[
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[
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[
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],
"content": "An invoice is unique, so no: once paid, you cannot pay an invoice again.\n\nYour phone should be online to receive payments, I have received payment while the app was running in the background, but never tried with the app off.\n\nMaybe give it a try yourself. You can put money into a web wallet like coinos and coinos.io and then try to send it back after swiping away the app or whatever you want to try.\n\nAnother wallet is Zeus. They offer a lightning address which is something you can give to multiple people and they can pay as many times as they like and as much as they'd like.\n\nThey also support always running in the background mode although it could drain your battery quicker.\n\nFinally they also support a semi-trusted offline payment solution. For this, you should open the app at least once a day to make sure payments are settled properly, and there is a fee involved for the service for each payment.",
"sig": "9993022fc2cd7d146ad00e4e8af0f33a3fa737b36010bf170d2bbe9bddd92ed2b885fb1d4c6830840ae79818b60c4a56bdf92e826cb65071b1ddf1b69ac46980"
}