Unlocking after restart

Hello,

I updated my P9, and after installing the update, the phone restarted. It asked me for the PIN code, then it requested your unlock password is required after restart (16 digits).
I never created this password!!!
If anyone has a tip to unlock it and especially to remove this password after restarting, I would be interested.
Thank you in advance for your responses. ...

Configuration: iPhone / Chrome 51.0.2704.81