iPhone 18 Pro sometimes looks at its owner like a stranger: the screen is on, notifications arrive, but unlocking with your face doesn't work. The passcode saves the day, but using the phone in gloves, with wet hands or on the run is inconvenient again.
First, the main twist. Apple released iOS 27.0.1, and this is not a routine update with "performance improvements". Inside is a fix for a critical Face ID bug on the iPhone 18 Pro. That is, in some cases the phone doesn't see your face not because of the camera and not because of your features, but because of an error in the software itself. And it is cured by firmware, not by repair.
So the first step is Settings, General, Software Update. Wait for the download, install 27.0.1 and let the phone reboot on its own. The bug should go away together with the old system version.
Didn't help — we go deeper. Open Face ID & Passcode, reset Face ID. The phone will ask you to set it up again: calmly, in normal light, without the sun in your face, hold your face in the frame and slowly turn your head around the suggested circle. Sometimes after major updates the system needs to "remember" the person again: the old blind spot from the faulty firmware gets overwritten by the new record.
If that changed nothing either — reboot. Not locking the screen, but a full power off and on. This resets temporary sensor glitches and helps more often than people expect.
And now about the hardware. If after updating to 27.0.1 Face ID is still silent, then the problem is no longer in the software: the front camera, the infrared emitter or the whole module is to blame — something that can't be fixed through settings by hand. That is treated at a technician's bench, with diagnostics and disassembly. But before the phone reaches us, all three steps from this text are worth honestly going through — often a visit over a non-working Face ID is closed at home, without a single screw.