Resetting Face ID from Settings > Face ID & Passcode resolves most post‑update failures on iOS 26. If Reset is blocked or greyed out, security settings may be requiring Face ID first. The sections below walk you through proven fixes, starting with the quickest win and moving toward service if hardware is flagged.

Method 1: Reset Face ID (and handle Stolen Device Protection)

Step 1: Open Settings > Face ID & Passcode, authenticate with your passcode, and tap Reset Face ID. This clears existing facial data so you can re‑enroll cleanly.

Step 2: Tap Set Up Face ID and complete two slow, full‑circle scans. Do this in steady, even light with the phone about 10–20 inches from your face to improve first‑try unlocks.

Step 3: If Reset Face ID is greyed out or the action requires Face ID you can’t provide, turn off Stolen Device Protection in Settings > Face ID & Passcode. A security delay and a familiar‑location requirement may apply before you can change this setting.

Step 4: After setup, verify the toggles for iPhone Unlock, iTunes & App Store, Wallet & Apple Pay, and Password AutoFill are on. Test by locking the phone and authenticating in at least one app that uses Face ID.

Method 2: Clear obstacles, check angle and distance, add an alternate look

Step 1: Inspect the TrueDepth area at the top of the screen. Remove cases, covers, or screen protectors that overlap the sensors, and wipe smudges or dust so the IR projector and camera have a clear view.

Step 2: Make sure your eyes, nose, and mouth are fully visible. Some sunglasses block infrared light; if unlocks fail with certain lenses, test without them to confirm.

Step 3: Hold the phone an arm’s length away (about 10–20 inches) and face the camera straight on. On supported iPhones, Face ID works in portrait and landscape; if you have an earlier model, use portrait orientation as required.

Step 4: If your appearance varies significantly (hair, glasses, protective gear), add an alternate look in Settings > Face ID & Passcode > Set Up an Alternate Appearance to improve recognition consistency.

Method 3: Reboot and update to the latest iOS 26 build

Step 1: Restart the iPhone to clear transient glitches. Power off, wait 10 seconds, then power on. After reboot, test Face ID for unlocking and a purchase prompt to confirm reliability.

Step 2: Install the newest iOS 26 patch via Settings > General > Software Update. Point releases often fix early camera/Face ID issues, and users have reported recovery after updating.

Method 4: Reset All Settings (no data loss)

Step 1: Go to Settings > General > Transfer or Reset iPhone > Reset > Reset All Settings. This reverts system settings (Wi‑Fi, Bluetooth, location/privacy, etc.) without erasing your content.

Step 2: After the device restarts, revisit Settings > Face ID & Passcode, ensure Face ID features are toggled on, and test unlocks and in‑app authentication. Rejoin Wi‑Fi and re‑pair Bluetooth accessories as needed.

Method 5: When camera and Face ID fail together, or Face ID setup is unavailable

Step 1: Open Camera and a third‑party app that uses the camera. If you see a black viewfinder or repeated crashes across apps alongside Face ID issues, the problem is system‑level or hardware‑related.

Step 2: If the behavior persists after Method 3 and Method 4, arrange diagnostics and repair. Start a case at Contact Apple Support or book an Apple Store/Authorized Service Provider. Only trained technicians should service the TrueDepth system; improper repair can damage safety mechanisms.

Step 3: If you recently replaced parts, be aware the Parts & Service History screen may report a Face ID component issue. Service can verify whether a sensor is out of spec even if Face ID intermittently works.

Method 6: “Face ID Issue Detected” in Parts & Service History but unlocks still work

Step 1: Confirm the notice in Settings > General > About > Parts & Service History. Take a screenshot for your records in case the message disappears after a reboot or update.

Step 2: Update to the latest iOS 26 build and monitor Face ID. These flags can coincide with post‑update anomalies that later stabilize with patches.

Step 3: Contact Apple Support to document the flag and schedule an inspection. Even if Face ID currently works, a flagged component may become unreliable, and an authorized diagnostic creates a service trail.

Step 4: Avoid third‑party repairs on the TrueDepth system. These components are paired and require Apple calibration to maintain Face ID function and safety.

Last‑resort options when Stolen Device Protection blocks changes

Step 1: If Face ID is completely unavailable and security settings require Face ID to turn features off, back up your iPhone first (iCloud or a computer) to preserve data.

Step 2: If you cannot proceed and urgently need access without Face ID, erase the device using Find My on the web or another Apple device, then set it up again with your Apple ID. After setup, you can skip Face ID and operate with a passcode until service confirms hardware status. Note that Activation Lock will require your Apple ID credentials.

Most iOS 26 Face ID problems clear after a clean re‑enrollment or a small iOS patch; if setup is blocked or the camera fails system‑wide, schedule diagnostics so hardware can be ruled out or repaired promptly.