Payment failure

Payment failure when using the fingerprint scanner to pay
1. Make sure the fingerprint payment is enabled in the app.
2. Check if the issue is caused by a bad network.
3. Open Settings--Security&Lock screen to check if the fingerprint is added.

Low unlock rate

The frequency that unlocks the phone successfully is low
Fingerprint scanner failure
The fingerprint scanner doesn't work.
Regarding the 3 issues listed above, check whether any reaction or vibration occurs during the fingerprint unlock
1. If no reaction occurs during the fingerprint unlock
    a). check if it is caused because of pocket mode. 
    b). It is recommended to wipe the fingerprint sensor clean and try to unlock.
    c). Re-add a fingerprint. If the issue still persists, contact OnePlus for after-sales support.

If the device vibrates during the fingerprint unlock:
If the device vibrates but doesn't unlock during the fingerprint unlock process, it is recommended to wipe the fingerprint clean and try to unlock.

Please back up all the data, clear cache and flash to the latest OxygenOS version, if the issue still persists apply for after-sales service.