Critical: No CGM Updates - Loop Failure

[TravisWhip]

CRITICAL

This is a critical issue as Loop is no longer functional!

Loop will only work for a short while if I manually enter a BG value.

Description of Bug

Randomly Loop will stop receiving CGM updates and halt all dosing.

Dexcom App and Direct-to-watch are able to get CGM updates just fine, however Loop is not receiving any CGM updates.

I have raised this issue in the past on Zulip (https://loop.zulipchat.com/#narrow/channel/148543-Loop/topic/Loop.20Failure/near/479067306). In the past I was able to get around this issue by:

1. Delete CGM in Loop
2. Quit Loop
3. Quit Dexcom G7 App
4. Forget all Dexcom sensors in Bluetooth settings
5. Open Dexcom App & add G7 as CGM
6. Open loop app
7. Wait for pairing request from sensor

However, this time I cannot get around this issue.

Issue Report

Here is an export generated after updating loop to 3.4.4 (57) from develop 3.3.0 (57).
Export-20241119T013430Z.zip

After updating to 3.4.4 and still having the same issue I deleted Loop on my phone and all data, and re-installed Loop fresh. After doing this I still have the same issue. Here is another export after completely re-installing Loop:
Export-20241119T020829Z.zip

Pictures/Video

After deleting and re-adding the Dexcom G7 CGM, the CGM never connects / updates:
Full Size Image

Here is a short video showcasing that Loop has not updated in awhile and that the CGM is just "scanning":
https://github.com/user-attachments/assets/e847688b-facf-4a44-8577-ad3c7580d876

To Reproduce

Unknown at this time.

Expected behavior

Loop should get CGM updates while Dexcom G7 App is receiving updates.

Metadata

Phone

• Hardware: Iphone 12 Mini
• OS Version: IOS 17.5.1
• Watch OS: 10.6.1

Loop Version

• Version Number: 3.4.4
• Repo: LoopKit/Loop

CGM

• Device: Dexcom G7
• Manager app: Dexcom App

Pump

• Manufacturer: Omnipod
• Model: Dash
• Firmware version: N/A

Additional context

This issue has happened to me in the past and I was able to get around it by forgetting all Dexcom Bluetooth devices. However, this time doing these steps has not resolved the issue. Loop is currently unusable.

[marionbarker]

This must be so frustrating for you.

It might be helpful to see your Loop Report - the Dexcom traffic is included in there. (Loop, Settings, scroll down to support and tap Issue Report.)

I'm baffled by these reports. Yours is not the only one.

Some people reported it got better with the next sensor.
Some people used the procedure you listed successfully.
Did you add a phone reboot after forgetting all the bluetooth devices?
Did you wait for the sensor to first pair with the Dexcom app and the first CGM value be reported, and only then restart the Loop app?
Do you have other bluetooth devices connected to the phone?
Do you have any other apps on the phone trying to interface with the G7 (xDrip4iOS, Trio, Suggah, etc.)?

[motinis]

I wonder if it might be possible to work around this by implementing a new "Apple Health" CGM - basically it would be querying Apple Health for updates to BG. G7 App can write that data.

[marionbarker]

Dexcom app writes to Apple Health with a 3 hour delay. Not useful for looping. However, you could try using Dexcom Share as CGM. It requires internet and isn’t an idea solution but it should work.

[scottf51]

Out of interest does loop seem to hang when you open it or get very laggy when not working ? Just remembering an issue I had a long while back with G6 where something went screwy with apple health integration . Over a period of time the apple health data would build up and cause instability , when I turned off Dexcom writing to apple health and cleared the health data it was ok. Of course do not do this if you care about what is in apple health It’s a long shot and I think a fix was pushed ages ago for this issue , but since you seem to be in a real bind thought even a long shot was better than no shot Sent from my iPhoneOn 19 Nov 2024, at 02:10, Travis Whipple ***@***.***> wrote: Describe the bug Randomly Loop will stop receiving CGM updates and halt all dosing. Dexcom App and Direct-to-watch are able to get CGM updates just fine, however Loop is not receiving any CGM updates. I have raised this issue in the past on Zulip (https://loop.zulipchat.com/#narrow/channel/148543-Loop/topic/Loop.20Failure/near/479067306). In the past I was able to get around this issue by: Delete CGM in Loop Quit Loop Quit Dexcom G7 App Forget all Dexcom sensors in Bluetooth settings Open Dexcom App & add G7 as CGM Open loop app Wait for pairing request from sensor However, this time I cannot get around this issue. Attach an Issue Report Here is an export generated after updating loop to 3.4.4 (57) from develop 3.3.0 (57). Export-20241119T013430Z.zip After updating to 3.4.4 and still having the same issue I deleted Loop on my phone and all data, and re-installed Loop fresh. After doing this I still have the same issue. Here is another export after completely re-installing Loop: Export-20241119T020829Z.zip Video https://github.com/user-attachments/assets/e847688b-facf-4a44-8577-ad3c7580d876 To Reproduce Unknown at this time. Expected behavior Loop should get CGM updates while Dexcom G7 App is receiving updates. Phone Hardware: Iphone 12 Mini OS Version: IOS 17.5.1 Watch OS: 10.6.1 Loop Version Version Number: 3.4.4 Repo: LoopKit/Loop CGM Device: Dexcom G7 Manager app: Dexcom App Pump Manufacturer: Omnipod Model: Dash Firmware version: N/A Additional context This issue has happened to me in the past and I was able to get around it by forgetting all Dexcom Bluetooth devices. However, this time doing these steps has not resolved the issue. Loop is currently unusable. —Reply to this email directly, view it on GitHub, or unsubscribe.You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[TravisWhip]

So for the time being I am using a Dexcom Share CGM - but this requires constant internet connection.

Environment

Here is my current environment, please let me know if there is anything else that is noteworthy.

CGM Related Apps

I am not using any other application for CGM monitoring other than the Dexcom G7 app and Loop.

Apple Health

Only Loop is writing CGM data to Apple Health. My Apply Health history ends where loop initially failed. Dexcom G7 has been stable and reporting values since this issue started to now - no issues with Dexcom G7 directly (that I can tell).

Issue Reports

Hello @marionbarker, I have taken two Issue Reports and attached them below along with some context around them.

Issue Report - Dexcom Share CGM

This issue report was generated after using Dexcom Share as a CGM since re-installing Loop last night (around 9pm, EST).
DexcomeShare_Loop Report 2024-11-19 11_22_22-05_00.md

Issue Report - Dexcom G7

... While gathering this report the Dexcom G7 started working again...

This issue report was generated after switching to using a Dexcom G7 CGM in Loop after the first report was generated. I expect to have CGM readings every 2nd and 7th minute.

After exporting the first logs I performed the following:

1. Removed Dexcom Share as CGM in Loop
2. Added Dexcom G7 as CGM in Loop
3. Deleted Dexcom Bluetooth from Bluetooth Devices in IPhone Settings (around 11:21 AM EST)
4. Opened Dexcom G7 App to wait for Bluetooth pairing request
5. At ~11:22AM EST I got a Bluetooth Pairing Notification
6. Dexcom G7 App updated with CGM reading for 11:22
7. Went back into Loop and there was no CGM reading for 11:22
8. From 11:27 onward, Loop was able to get CGM readings, but did not backfill for the 11:22 CGM value
9. Loop works fine. CGM value for 11:22 is still missing in Loop.

DexcomG7Loop Report 2024-11-19 11_48_17-05_00.md

Quick Investigation

Comparing the DexcomShare and DexcomG7 issue reports, I can see a Device Communication Log I can see that at 11:23 AM, Loop tried to read from Dexcom:

* 2024-11-19 16:23:04 +0000 G7CGMManager  error Sensor error Error enabling notification for authentication: unknownCharacteristic

This looks to the 11:22 AM CGM value I am missing in Loop. I wonder if this is the error I was having yesterday (and in the past) preventing Loop from getting updated CGM values.

From this point on, I can see G7CGMManager logs for Connecting, Reading, Disconnecting - every 5 min as everything is working now. Example of log grouping:

* 2024-11-19 16:33:04 +0000 G7CGMManager DXCMqb connection Sensor connected
* 2024-11-19 16:33:05 +0000 G7CGMManager DXCMqb receive Sensor didRead G7GlucoseMessage(glucose:Optional(90), sequence:2187 glucoseIsDisplayOnly:false state:ok messageTimestamp:654805 age:6, data:4e00d5fd09008b08000106005a0006ff57000f)
* 2024-11-19 16:33:10 +0000 G7CGMManager DXCMqb connection Sensor disconnected: suspectedEndOfSession=false

Critical Event Logs - After Loop started working again

Since loop started working again, here are the critical event logs after loop started working:
Export-20241119T163157Z.zip

Current Status

Loop is now working again with the Dexcom G7 sensor directly... I am not sure what has changed from last night to now, other than running with the Dexcom Share CGM for the time being.

I am now able to use the Dexcom G7.

[andrewhemp]

My G7 just started having this same issue not uploading readings. It started at 12:05pm

Loop Report 2024-11-19 125616-0600.md

[TravisWhip]

@andrewhemp, to keep this thread clean, is there any additional context / logs you can provide in addition to what I have provided?

PS, use Dexcom Share as your CGM for the time being. Then every few hours try using the Dexcom G7 CGM until it works - at least that's what I did.

[andrewhemp]

@TravisWhip mine started working after awhile. I removed my CGM from loop, airplane mode, closed all apps and restarted phone. Not sure what was going on, I did notice the Dexcom servers were down when I tried to use share at first.

[alliemakes]

We have not been able to get the G7 to pair at all with Loop. We are a new to Looping and this is a new build and just trying to get everything set up and it just says searching. We have tried all the above steps to get it to connect: deleting app, deleting dxm values in bluetooth and shutting down apps and restarting. It will not connect to Loop. It is displaying in the Dexcom app and sharing to the follow app.
I am unsure what Dexcom Share is, unless you mean Dexcom Follow. If it is the Follow app, I am unsure of how to make that work together. All help is very appreciated.Thank you

[TravisWhip]

@alliemakes, it's a CGM option in Loop.

See the CGM section of Loop's documentation here: https://loopkit.github.io/loopdocs/loop-3/add-cgm/

[marionbarker]

There is an open PR to G7SensorKit that is improving G7 connectivity as long as the Sensor is communicating with the app. It is not perfect and some people are still having trouble.

Please see: LoopKit/G7SensorKit#33

This can be added to released version of Loop (see G7 Missing Readings option) using a the Customization Select Script:

• https://www.loopandlearn.org/custom-code/

[timd24]

Following this issue closely. This is the most challenging bug I’ve seen in the app in many years.