goTenna will retry sending your message a few times, and then if it still doesn't go through, will alert you that it hasn't been delivered. At that point you ca

goTenna will retry sending your message a few times, and then if it still doesn't go through, will alert you that it hasn't been delivered. At that point you can try again manually. There are delivery confirmation receipts for 1:1 messaging but not for groups as that's a networking nightmare (e.g. not even Whatsapp or iMessage does that).