I experience the same problem. Fingerprints are still stored and functioned well until recently. But now they won’t do the trick for unlocking the phone. Also for me: deleting the prints, rebooting and re-registering worked, but after a while they stop working…
My guess is, that it has something to do with failed attempts: if you have the phone in your pocket it may try to unlock often when it slightly moves inside. Is it possible that there is not only a counter for each individual attempt to unlock, but also an overall count?
Thx, I just wanted to make sure there wasn’t a FP3+ exclusive update already I missed (By the way, here’s a list of all updates: ✏ FP3 OS updates - changelog & OTA links). October update didn’t fix anything for me.
I was having this issue after updating my system to Android 10, but the “fingerprint” option under settings → security wasn’t even visible, and it did not register anything at all with the fingerprint reader, not even an inaccurate print.
While in settings → security, I accidentally clicked on “security update”, and apparently that was not up to date, so I updated it and now my fingerprint reader works as perfectly as it did before.
Perhaps check that all your updates are finished? Mine just needed to restart, but hadn’t given me any push notifications about it so I didn’t know.
Since acquiring my FP3+ in September I’ve never been able to use the fingerprint scanner / reader satisfactorily, but I’ve often had problems with other fingerprint scanners so I wasn’t surprised.
I had entertained the idea of trying the adhesive tape trick but never got round to it. However since updating to the latest 10 version 8901.3.A.0107.20210513 it’s been working perfectly. I can’t be sure this is due to the update but it seems so. No problems with reboots either. Very short taps work fine.
Not sure I have the same issue as yours, but here’s mine: if I don’t use the fingerprint immediately after the boot, I can’t use the fingerprint anymore to unlock the screen.
Here is what happens:
Boot the phone and wait until the lock screen appears (the one with the clock, by default)
Either unlock the phone using the pin (and not with the fingerprint) or wait until the screen turns off
When you try to unlock the phone later, you can’t use the fingerprint method (nothing happens if you touch the sensor) and you must use the pin (or other method) to unlock
Now reboot and use the fingerprint immediately when the first lock screen appears: it asks you to type your pin (as it’s the first unlock since reboot, that’s normal) but then you can use the fingerprint every time you want to unlock the phone.
That’s a good idea but currently I no longer succeed in reproducing the problem .
Basically it happens when I switch my phone off for the night (if I don’t need the alarm clock). When I boot it again in the morning, I encounter the issue.
I just tried to reproduce by switching off, wait a minute, boot, wait the lock, a minute again, but then I can unlock using the fingerprint (it asks me to type the phone pin as it’s the first time after the boot, but the fingerprint sensor is well on).
I’ll pay attention to your suggestion and come back to you next time I’ll sleep in .
This is an old topic so I thought it would be good to wrap it up with the following summary. I’m marking this post as “Solution” so that the topic is seen as solved, but it’s the cumulated experience of all the contributors to whom thanks. The information here concerns FP3 standard Fairphone Android (stock OS).
Make sure Android is up to date
Settings > System > Advanced > System update
Make sure Google Play is up to date (this can be more recent than the System update)
Settings > About phone > Android version > Google Play system update
Clean the scanner if really (visibly) dirty
Delete all registered finger prints
Settings > Security > Fingerprint
Reboot the phone
Set up at least one finger.
It can help to record the same finger more than once.
When registering the fingerprint, at each touch, leave the finger on the sensor for about 3 seconds until told to “Lift finger then touch sensor again”.
Once at least one finger has been registered, you can use it to unlock the phone except the first time after a reboot. Using the fingerprint is not an option listed under “Choose screen lock” which is managed separately and offers None, Swipe, Pattern, PIN or Password.