I use fingerprint to unlock my phone (Nokia 6 TA1033, upgraded to Oreo 8.1, not rooted). Sometimes it doesn't let me use fingerprint and asks for a password instead "for better security". I can't predict when this happens. Is there a way to prevent this? Like maybe unlock with a password on every nth wake-up so that I don't have to type the password in an uncomfortable situation?

Sometimes it is just really inconvenient to type the password, especially when your password is long. Also I believe in public places it is better to unlock with a fingerprint because then no one can see what you type.

  • Probably a Nokia-specific behaviour - never had that on LineageOS 15.1 (which supposedly has the AOSP behaviour).
    – Andy Yan
    Commented May 17, 2018 at 15:13
  • It happens on my Pixel XL and has since day 1. Its random, and I recall reading about others having the issue and that it was a bug of some sort. Running P now and it still does it. :shrug:
    – user202027
    Commented May 17, 2018 at 19:26

2 Answers 2


On stock Android, a backup authentication method is required after 5 failed attempts, or 48 hours since the last time that backup authentication method is used.

Using a screen off app will trigger this immediately, as that's how they trigger the screen off.

  • I am sure it happens on my Nokia 6 after 5 failed attempts. I don't know if 48 hours. I wanted to consistently test it but I keep forgetting. Please state the source of information. If this is what you observed on a particular phone please state model and android version. Thanks. Commented May 29, 2018 at 19:44
  • 1
    support.google.com/pixelphone/answer/6285273?hl=en while this specifically targets the Pixel, my understanding is that Google doesn't change that behavior brought in from AOSP, so if Nokia didn't change it, it will also behave this way.
    – plttn
    Commented May 29, 2018 at 19:47
  • Thanks. I think that is the case because part of HMD's marketing strategy is about pure android. Commented May 30, 2018 at 20:48

In Android 8.1, password input in required when the phone is rebooted or is locked by administrator (e.g. a screen locker app). You may use a pin-code instead to ease the unlock process. Face recognition is also a good way to unlock your phone.

  • I know it happens after reboot but it also seems to happen randomly. It is probably phone specific behaviour. Thanks Commented May 18, 2018 at 16:52
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    @Puzzledstudent Today I got an idea what might have triggered the "randomly": on my device, it seems that whenever whatever "touches" the FP sensor, the device wakes up and expects a fingerprint. I was wondering today why the device (being in airplane mode) vibrated that often in my breast pocket. Later I found the FP unlock icon was gone. Only now (about 12h later) it suddenly became available (and working) again. Transferred the device to a belt pocket now which is hard enough not to reach the sensor. Will see if this does the trick long-term :)
    – Izzy
    Commented Oct 1, 2018 at 22:18

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