My brother can unlock my Iphone X with his face id

I've seen other comments on this question. Where were you standing when your brother opened the phone? If it was anywhere within range of the camera it was your face that opened it. Try again with you behind the phone.

One thing to try is to redo your face scan on the phone, and make sure he is out of range when you do it.

If he knows your iCloud ID that's a very bad thing; change your password and make him get his own iCloud ID. Anyone with access to your iCloud ID can access pretty much all data on your phone.

As another user I can't do anything, but make a genius bar appointment and take your brother along to demonstrate the problem to the technician. Genius Bar Reservation and Apple Support Options - Apple

That is normal and was stated in the keynote and here -About Face ID advanced technology - Apple Support

There is nothing wrong with the device only your understanding of what should have happened. Do not let your brother handle the phone if you do not want him gaining access.

Hi nijo4joy,

A face id is easier to unlock than a finger id or a password. Especially if a relative tries to unlock. So there's nothing wrong with you Iphone X.

Greeting,

Fleurg

fleurg wrote:

Hi nijo4joy,

A face id is easier to unlock than a finger id or a password. Especially if a relative tries to unlock. So there's nothing wrong with you Iphone X.

Greeting,

Fleurg

That is exactly the opposite of what Apple says. I wonder who we should believe?

Apple’s published data from extensive testing:

Fingerprint - 1 in 20,000

Face ID - 1 in 1,000,000

it found that identical twins could fool it sometimes, but family members never. So there is something else going on in this case.