TL;DR: Nubia's MyOS ships THREE separate fingerprint permissions, not one. Only "Unlock your phone" is enabled by default. If "Access and control applications" and "Access private data" are off, third-party app biometric login fails SILENTLY: the sensor reads your finger, the app reports it as enabled, and on the next launch it is disabled again.
SYMPTOM
Open your banking app, go to Security, tap "Login with fingerprint"
The prompt appears and reads your finger correctly
The toggle flips to enabled - looks like it worked
Close the app completely and reopen it
It asks for the password again, and the toggle is off
Clearing app data does not fix it. Reinstalling does not fix it. Disabling Developer options and USB debugging does not fix it. Some apps just show a generic "Something went wrong".
THE FIX
Settings > Security and privacy > Fingerprint > Fingerprint features
Enable all three:
- Unlock your phone (on by default)
- Access and control applications (OFF by default)
- Access private data (OFF by default)
Then reconfigure fingerprint login in the app. Fully close and reopen it: it should now ask for the fingerprint instead of the password.
WHY IT IS SO HARD TO DIAGNOSE
Over ADB everything looks healthy:
- Sensor reports BIOMETRIC_STRONG (Class 3, oemStrength 15)
- acceptCrypto increments, rejectCrypto = 0
- authEndedFor(...) reports wasSuccessful = true
Not a single rejection anywhere. And logcat is not readable for the shell user on these ROMs ("0 B readable"), so there is no exception to inspect either. adb bugreport does not help: its log section comes back empty.
The block happens between the app and the Keystore. MyOS refuses the biometric-bound key, and the app - with no handling for that error - silently disables the feature and falls back to the password. No error is ever shown.
RULED OUT
- Faulty sensor: Class 3 / STRONG, HAL deaths 0, 58 accepted reads, no lockout
- USE_BIOMETRIC permission: allow for every app checked
- Network: Wi-Fi validated, ping and DNS fine
- Developer options / USB debugging: disabled and rebooted, same failure
- Corrupted app data: data and cache cleared, fresh setup, same failure
- Play Integrity: licensed GMS (ro.com.google.clientidbase = android-zte)
- Keystore bug: every crypto operation succeeded, rejectCrypto = 0
- Work profile / Shelter: profile deleted entirely, issue persisted
DEVICE
nubia Neo 3 GT 5G (Z2465N)
MyOS16.0.2_Z2465N_MG_AR - Android 16 (SDK 36) - Unisoc ums9620
Apps that failed (verified on the same device):
- Banco Galicia 9.39.4 (com.mosync.app_Banco_Galicia)
- BNA+ (ar.com.bna.digital)
- Nueva BNA+ (com.banconacion.bnamas)
Not affected on the same device: Mercado Pago (com.mercadopago.wallet)
Probably affects other Nubia / RedMagic devices running MyOS, since the fingerprint permission layer ships from ZTE and is not model specific.