So, My partner's phone is unlocking via my face but we haven't set up a 2nd face... I have access to his phone when he is driving so have used a passcode to unlock as face is refuses to unlock. All fine until now his phone is unlocking by my face. Now, we may both be male, shaved heads and wear glasses but I don't believe we are looking that much the same. So what has happened to allow it to unlock?