Default [Q] how to encrypt rooted galaxy note 2 i-317?

I used CF-Root to root my galaxy note 2 I-317. It works fine.

When I add my company's email which requests encryption on the device, it doesn't work well. I click "Encryption" button, the phone reboot and still shows a notification that I need to encrypt the device.

I tried to turn on/off knox, it doesn't help.

If you have any experience to make it work, can you share?