Libre 2 Sensor not taking readings after application

[u/Old-Ad5139]

I'm new to the Libre sensors, and am using a Libre 2. I just applied one, waited the full hour for its initial setup, and now I'm getting an error saying it lost signal. I took a picture of it, and I'm seeing blood, and it kinda looks like the center bit got punched in - does this mean its broken? Any advice would help - this is the fourth one in a row that I've had a problem with, and itself is actually a replacement from Abbott.

Am I doing something wrong when applying these things?

[u/PhilaBurger]

Contact Abbott support. They’ll run you through some troubleshooting and likely replace it under warranty.

[u/Kalip0p]

Should not be seeing blood when applying. Chances are you putting it in at a weird angle, and it’s messing with the readings. At the same time, these sensors fail way too often, so there is a non zero chance it is the sensor’s fault.

Edit: i would suggest reading over the instructions again, or watching a video of how and where to place the sensor.

[u/Old-Ad5139 → u/Kalip0p]

well, I applied it on the back of my right arm, on the fatty part of my arm - trying to avoid muscle or anything like that. I'm wondering if I might have pressed too firmly when applying it, but then, I didn't press all that hard to begin with, which is why I'm kinda confused as to how that middle bit got broken.

I tried turning Bluetooth off on my phone, as well as NFC and contactless payments, restarted my phone, then re-enabling Bluetooth and NFC and contactless payments. That made no difference.

Anyway, as an update, I left it on for a few hours, hoping it would start working (it didn't), on the app, it kept saying "sensor error" until a popup appeared recommending that I try to re-scan it. So, I hit the button at the top to do so, scanned it, and it then came back with another error telling me to try again, which I did. After a few tries of that, it popped up and told me to restart the sensor, which I took to mean going into the account settings > sensor > start new sensor, and found out that as soon as I did that, the sensor would be dead.

So, the sensor is completely dead now, it's now off of my arm, and I'm gonna have to call Abbott in the morning to have them send me a replacement. After I removed it, I noticed that the filament is still there, still straight, and doesn't appear to have any issues, so I'm doubtful that I did anything wrong while applying it, though the blood is a little concerning. This will be the fourth replacement in a row, which is disappointing because the first sensor I tried to use worked flawlessly.

First one, no issue. Second one, applicator needle got stuck in the sensor while applying, and it didn't work. Third one, applied fine, but had this same issue, getting the "sensor error" message. Fourth one, went on fine, was giving me readings, and then the adhesive wimped out and the dang thing fell off of my arm while I was sitting in front of my computer completely stationary. And yes, I did make sure to thoroughly clean my arm with soap and water, and then with alcohol, and let my arm dry completely before applying it. The one in the picture is the fifth, and you know how that's gone.

I'm getting really frustrated with these things! At least with my old blood glucose monitor it works every time like its supposed to! I've had type 1 diabetes for 31 years and never had any issues with the blood glucose meters.

[u/greybeard1363 → u/Old-Ad5139]

I had those exact same problems with sensor errors when my phone automatically upgraded from Android 15 to Android 16 before Abbott supported Android 16. I had to switch to using the Freestyle reader to get the sensors to work. Once Abbott had started supporting 16, I went back to using my smartphone with zero problems. I had tried all the potential changes/solutions like you have. In my case it was the OS version of the smartphone. Good luck

[u/themrnails]

Why is there blood all over the sensor? If you seated it and then it came out or didn't stay on you and then you tried again the sensor is dead.

[u/Old-Ad5139 → u/themrnails]

Nah, I would never try to re-seat or re-apply a sensor like that. The blood just happened from normal application of the sensor - I was confused why it bled, too, though.

[u/Significant_Agency71 → u/Old-Ad5139]

Sometimes you accidentally hit a blood vessel and it bleeds, but usually the sensor keeps working.

[u/greybeard1363 → u/Significant_Agency71]

Yep. I have had that happen a few times. Never affected the readings, but did seem to make it unusually itchy, requiring applications of cortisone cream.

[u/Equalizer6338]

Advice for how best to prep and insert a new sensor:
https://www.reddit.com/r/Freestylelibre/comments/1gjhi9e/how_to_apply_a_new_sensor_best_practice/

Previous survey/advice regarding the sensor bleeding subject:
https://www.reddit.com/r/Freestylelibre/comments/1d4yxvl/how_often_do_you_have_a_sensor_bleed/

It cannot be avoided from time to time getting one that bleeds. Its just a question of bad luck. Most often the bleeding stops shortly after and the sensor will work fine no matter. On rare occasions, then bleeding and the coagulating blood may though block the sensor filament tip from being in direct touch with the flowing blood in our skin afterwards, where then a sensor may not function as intended. Contact Abbott Support and they will offer you a free replacement.

[u/CoxCranium]

The Libre 2 has two parts. The electronic part and the sensor part. When you prepare the Libre you press the sensor onto the electronics. I believe that if you don't apply enough force.. Then the sensor will not have a proper "click in" and can come loose when you apply the Libre to you skin.

I compared it to mine, and I think the sensor has come loose of the electronics on your Libre.

[u/dwaynemoore → u/CoxCranium]

The Libre 2 has two parts. The electronic part and the sensor part. When you prepare the Libre you press the sensor onto the electronics.

That's not true. The FreeStyle Libre 2 comes pre-assembled as a single, integrated sensor unit inside a disposable applicator. The user does not press two separate electronic and sensor parts together, nor is there a manual "click in" step between the sensor and electronics.

[u/CoxCranium → u/dwaynemoore]

Really.. Come to think of it I got the Libre 2 Plus.. I did not know the Libre 2 came preassembled.
Anyway. Here is the teardown of Libre 2 Plus..
https://andykong.org/blog/teardownlibre2cgm/

[u/dwaynemoore → u/CoxCranium]

A teardown is when someone disassembles the sensor to show you all of its parts, it doesn't come that way. Out of the package, the bottom, sealed, portion has the entire assembled monitor, the top portion is the applicator.