Apple says that its new face recognition system is so secure that the chances of a stranger being able to unlock it are one in a million. Unfortunately for Apple, the first time it showed off the new security feature in public, it failed.

Craig Federighi, Apple’s vice president of software engineering, was on stage in the Steve Jobs Theater on Tuesday to showcase the innovative features of the $999 iPhone X. First up Federighi had to unlock the new device. “Unlocking it is as easy as looking at it and swiping up,” Federighi said. But when he looked at the front-facing camera above the screen, the phone didn’t seem to recognize him and went to the passcode screen.

“Ho, ho, ho” Federighi responded as he wiped some sweat from his brow. A veteran of Apple demonstrations, Federighi looked slightly worried before saying: “Let’s go to backup here.”