The problem is that I cannot delete them, when I click on any of them I see DELETE button where I edit a name for a partucular fingerprint but it does not delete.
That's already the recovery mode. At that point press and hold the power and vol-up buttons (in this order) together, then release them to call the recovery menu.
If you change the screen lock method to an unsecure type (None or Swipe), that should also remove your existing fingerprints, so after setting a secure unlock method again, you can set your fingerprints again.
Hello. What's your current system version? I've the V2.0.017 but I don't know if there is a new one...system update tell me that mine is the last one but I'm not sure about that.