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New phone - NFC won't scan L2 sensor

Henryhoggle

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Mytholmroyd
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I live in the UK and bought a new Doogee phone for a change. It's usually marketed to US & Aus, but has amazing features so thought I'd try it. During setup I've discovered problems with the NFC on the phone. The NFC works with payments..but apparently it is limited by market/region which therefore doesn't support Libre2 EU sensors
(I incorrectly assumed NFC was generic hardware that worked with any nfc enabled device anywhere in the world. Apparently not

When I place the phone near the L2 sensor it vibrates twice and displays the same scan error 335 (with lengthy description stating it can't scan the L2 and I should try again). I've rung LibreSupport and given them the event log to investigate and send new sensors in the meantime.

I'm not hopeful this is fixable. 3 options have been mentioned on similar threads:
1. Add VPN to phone to remove regional/market restrictions ?
2. Open permissions of the Libre2 sensor ?
3. Install an NFC scanner app ?

Are any of these even possible? Has anyone come across this and found a fix
 
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Curious one. I had a quick look at NFC specs and they are not region-specific - the same chips and radio settings are used worldwide, unlike say WiFi where there are 11 2.4Ghz channels available for non-licensed use in the US while there are 13 available channels in most other countries. NFC is indeed the same everywhere.

That's not to say the use of specific devices in specific regions is not restricted though. Medical devices must be approved by the regulatory authority in the market for which they are sold - so the FDA in the US, the EU regulators in the EU, Japanese in Japan and so-on. Both the app and the sensor need approval as a paired system before it can be sold as a medical device. For this reason when you go to download the LibreLink app it will give you a version that is specific to your region, determined by the region of your app store, and the app probably won't work with sensors sold in other regions. You might have a regulatory boundary problem that's not due to NFC.

Are the region settings on your phone working correctly as a UK-based phone? You might be able to tell from the title of the LibreLink app in the app store - when I search for LibreLink in the Google Play store the title of the result I get is 'FreeStyle LibreLink - IE' denoting that the app version I'd be downloading is the one specific to Ireland. Do you see 'UK' at the end of the app title in the store? Another quick way to test store region is to search for an app that is only available in the UK - for example 'BBC iPlayer'. That's an app that's not available on my phone.

I'm not sure how app store regions are set - it might be a phone setting or it might be based on IP address or similar as a way to determine the phone's location. The VPN solution might work if it's IP address based and if the phone is currently in a country outside of the regulatory jurisdiction in which the sensor was purchased. I.e. - if you bought a sensor in the UK but your phone was in the US, using a VPN service to fool the app store into thinking your phone was on UK soil might allow you to download the matching app version.

Beyond that I don't have any ideas. I don't know a lot about NFC as applies to this problem beyond the fact that at a hardware level the standards devices are built to are identical worldwide.
 
Henryhoggle said:
When I place the phone near the L2 sensor it vibrates twice and displays the same scan error 335 (with lengthy description stating it can't scan the L2 and I should try again).
Click to expand...
Hi,

Have you placed the NFC area directly to the sensor, holding steady for a while?
Or sort of “Jedi mind trick” waived the device over the Libre?

Did you “clone” from your old phone? Which usually grabs purchased apps from your installed history. (free ones too.)
You might need to log back into accounts. I can’t remember if I needed to with librelink..
 
I don't think this is a regional lock issue as AFAIK Abbott have a different error message for that case.

This may be just a case of NFC unreliability. If you are getting the 335 error, then the Libre is able to realise that you are trying to scan the sensor (so NFC is working), but the scan does not complete.

My only suggestion is to try to find where on the phone the NFC sensor is located and try to hold that over the sensor. If you are like me, you might tend of move the phone about while trying to get it to scan - which could mean you start to get a signal and then move away before the scan is complete (which is why the 335 message talks about hold the phone steady).

I've changed my phone recently and haven't figured out yet the trick to scanning reliably so my Event log is full or 335 errors, but it does scan eventually.
 
Thanks for your thoughts!
I tried your great suggestion to search Play Store to identify any regional restrictions of apps returned from the search. Librelink app is displayed with a GB suffix so guessing that demonstrates the phone's marketing/region restrictions don't exclude UK?


Re NFC, it does make more sense to be a universal feature but Doogee Support tell me otherwise. I've asked them for more tech details that I can share with Abbot to confirm their thinking.


Anyways, if this phone is unrestricted for UK use...and NFC is in fact universal, then the issue can only be with the L2 sensor?
 
Yeah I know what you mean... finding the NFC sensor is tricky sometimes.

I did transfer my apps over from old to new phone. I needed to re-install LibreLink. It didn't require me to re-enter my credentials which bothers me a little. ...and LibreView.com login is screwed at the moment so I can't check if the install is registered properly to me or not. The app does display my name behind the burger menu top left though so perhaps I'm over thinking this?
 
Yeah...I'm kinda hoping the issue is this tbh. The NFC on this phone is temperamental so the issue may be a weak or laggy signal ...which then makes it much harder to find the sweet spot. That said, it could also be a weak/laggy L2 sensor too. Two replacement sensors are coming direct from Abbott so I'll find out soon enough.
 
Inside of the sensors is two small batteries and you can even see the NFC arial in the casing as I know as I had one fall off and fall to pieces on the floor and it was still working just didn't connect to my arm so I had a scope over it and that's what I found inside of it and the small batteries look like the LR44 kind that you had in little clocks many years ago and the other bits were chips so that the sensor can work but I use a iPhone 14 Pro Max and sometimes I don't find the sensor and I have to go looking for it and I get it eventually and when I have to do it manually it's just a quick scan but it depends on where you place if mine go on the back of my arms as I used to put them in the inside but it was losing the signal and I had to scan every time so now I'm getting the error messages once every few months and that's because I have placed the sensor in the wrong place on my arm but otherwise it works fine
 
Since the original post:
1. Doogee have confirmed NFC only works for payments..is limited by market/region and will not work with Libre 2/LibreLink.
2. Abbott's device compatibility guide does not include Doogee phones at all, so I have to assume Doogee has not been tested by them as yet.

It's a shame because the huge battery power of Doogee is perfect for the intensive battery usage of cgm. Maybe things will change in the future but for now Doogee is not a choice for T1D blood glucose monitoring in the UK

Useful refs:
1. Phone & watch NCF's - https://en.wikipedia.org/wiki/List_of_NFC-enabled_mobile_devices#Smartwatches
2. Device compatibility - https://www.diabetescare.abbott/support/manuals/uk.html
  1. Navigate to the Freestyle Librelink section.
  2. Locate the “Mobile Device & OS Compatibility” row
  3. Click on the PDF icon to open the compatibility guide
 
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When it's working correctly, the Libre connection really doesn't use that much battery. Mine is currently showing as 0.5% of my total battery usage.
I remember there was a bug in some earlier versions where it was consuming more like 50%, but that was fixed long ago.
 
I’ve got a 4300 mAh battery on my device with librelink & Diabox running in the background which can comfortably get me through the day..
 
Options would be to use the Bluetooth from the libre to pull data into another app (Shuggah, xDrip+ etc) and bypass the Librelink NFC scanning.

That way you could scan and start the sensor using the BG meter, and pick the readings up from your phone (I know that can be done using xDrip - not sure about Shuggah as not a user).

That opens up all sorts of other possibilities (BG on a watch, better reporting etc) as well, worth consideration
 
Why not try it with a different app but you still use the Libre Link app and you have to use the Libre Link Up app and then what you want to use as a app and then you can use it as normal your new phone as I had to do that to get it to work on my apple watch and now I get my results on my watch and phone and that is to the second and you have to use the same id for both in Libre Link apps for it to work but it will for you
 
I don't use a phone to scan. I had problems with apps in the past and when I tried to rectify they just played the blame game where Freestyle would blame the phone and the phone manufacturers would blame Freestyle.

I have continued to use the Libre meter - so there is only Freestyle to blame if it doesn't work properly, lol. I find the meter is also better as I don't have to carry a big clumpy (and heavy) smartphone around with me - especially when exercising.

Does anyone else use the actual freestyle meter reader rather than a phone and app?
 
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You still need to start up sensor via NFC. No other way.
 
Thanks for all the replies. I've been researching various approaches since the original post. Upshot is, unfortunately I can't use my kick-ass Doogee mobile because of the NFC issue (which is confirmed not to work with Libre sensors). Massive shame, but haho.

I'm successfully using my old Google 3XL as a burn phone really with both LibreLink and Diabox apps running on it. I manully NFC scan my Libre once a day and then 'force stop' to push ALL the days data to LibreView.

Diabox is mirrored to my Gwatch4, which is working brilliantly so far. Still got thing to sort like data and calibrating ,but on the whole, this setup seems to be giving me improved control.
 
Sounds a bit daft.
But from memory with the Diabox app I needed to put a code into it to allow the calibration feature.
Tap the icon of a Libre sensor on the Home Screen with the graph in the app, (below where it says “device status.”)
Again from memory “calibration mode,” should need a “cheat code” to activate it. The code is “GODMODE” if you get stuck?
The later Diabox builds might have done away with this,
Hope this helps?
 
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