I tried unlocking the device by Find My Mobile service, it was supposed to delete the lockscreen password, as well as Biometrics, I was able to access my phone. I thought problem is resolved and tried registering biometrics again, but it asked the password again. Now I thought restarting might fix this, but again, after restart, I'm stuck on lockscreen, and it doesn't accept any password. And I don't want to reset the phone, it has important data.
IF SOMEONE FINDS SOLUTION TO THIS, PLEASE COMMENT THE SOLUTION. (NO SUGGESTIONS FOR RESETTING THE DEVICE, PLEASE)