Sending a message looks like it works immediately, but receipt of the message is delayed by ~30 min

[carols10cents]

• I have searched open and closed issues for duplicates (I searched for "delay", "slow", and just looked through recent open/closed and didn't see my issue precisely)
• I am submitting a bug report for existing functionality that does not work as intended
• I have read https://github.com/signalapp/Signal-Android/wiki/Submitting-useful-bug-reports
• This isn't a feature request or a discussion topic

---

Bug description

When I am in a particular location that has low/slow cell signal, and I send a message, in the UI it looks like the message has sent successfully. However, the person I send the message to reports not receiving it until 20 or 30 min later.

I'm suspecting it's on my (the sending) side, but I'm not 100% sure. If this is actually on the receiving end, I'm happy to move this over to the iOS repo and get more details on that system.

Steps to reproduce

• I go to a location where the cell signal isn't great (I go there every weekday so I can reproduce this pretty reliably if needed)
• I send a message from my Android device to an iOS device, which appears to be sent successfully immediately
• Later I check with the person I sent it to, and they report receiving the message 20-30 min later than when I sent it.

Actual result: Message is delayed, even though it looks like it was sent
Expected result: Message sent and received within a few minutes, or an error saying the message wasn't sent

Device info

Device: Samsung Galaxy S10e
Android version: 12
Signal version: 7.11.4

Link to debug log

I'm not sure that we've captured these logs quickly enough after the reproduction-- please let me know if the relevant time is missing and I'm happy to try again. Also, I'm not sure if on the receiving end, if "immediately after the bug has happened" would be "when the sender has sent the message" or after the delay when the message is actually received -- please let me know.

I sent the message at 16:34 local time, and it was received at 17:04.

Android/sending logs: https://debuglogs.org/android/7.11.4/9a0a4e250b48cb7fec2e0fd8f8286ac244451b01c4ccbf3216b6c83ddecd66e7

iOS/receiving logs: https://debuglogs.org/ios/7.20.0/f3a3a974fbf6d8e104c2155ab901fe97cba43ee3353b3bf6da4b7dedf9cb563c.zip

[yarny2024]

Similar problem here. Did the update to 7.11.4 just before the problem. Sent a message, it got delivered, but after 8+ hours, it never showed as seen. The other person responded as well, yet, their messages never got delivered back to me on android. If I hadn't checked the desktop client, I would have never known.

https://debuglogs.org/android/7.11.4/0052f112cba7db8da08228e7645bc8ec29ec4022a8d5d23779f5ee5daaf0990a

[nicholas-signal]

hi @carols10cents, based on your logs, I see the initial 16:34:02.925 EDT send failed due to lack of network connectivity, retried, failed again, and finally sent on the third attempt at 16:55:55.867 EDT. Between the second and third attempt, there's a big gap of about 20 minutes where nothing happens in the Signal app. Is it possible that the app was killed by the system in the background, by a "Battery Saver" mode or similar?

@yarny2024 we had a minor service hiccup in the last day or so, which should be resolved now. Did the missing message show up?

[yarny2024]

They did show up after around 24h, but first I received the notification that the messages could not be delivered.

image

[carols10cents]

hi @carols10cents, based on your logs, I see the initial 16:34:02.925 EDT send failed due to lack of network connectivity, retried, failed again, and finally sent on the third attempt at 16:55:55.867 EDT. Between the second and third attempt, there's a big gap of about 20 minutes where nothing happens in the Signal app. Is it possible that the app was killed by the system in the background, by a "Battery Saver" mode or similar?

Interesting. I would have expected some sort of indication in the UI that the app is still working on sending the message, rather than looking successful?

I did not actively turn on any battery saver mode, but it's possible the system did something-- how would I go about checking on that and turning it off if so?

[nicholas-signal]

So just to confirm: you're receiving the single checkmark* on the message right away, even though it's not actually sent until later?

• https://support.signal.org/hc/en-us/articles/360007320751-How-do-I-know-if-my-message-was-delivered-or-read