Hello,
on my BL6000pro the fingerprint sensor suddenly stopped working, I thought I hade to reset the fingerprint, but after I deleted the existing fingerprint, the fingerprint options just disappeared.
I tried to reboot the phone many times, wipe cache partition, reboot in recovery mode, etc. I was wondering if this issue is related to the OS or the hardware, because I saw that also other brands have a similar issue. I also tried to turno on/off dark mode and turn off all unlocking options (for others it seems to have worked) but it still did not solve the issue.
For the moment I would prefer not to factory reset the phone if it is not sure to solve the problem, because I'm having trouble also doing the backup of the phone, and this would mean that I would have to manually set it again to my preferences.
Regards