If Face ID isn't working on your iPhone or iPad Pro — by Apple Support
Troubleshooting steps for Face ID: update iOS, check settings, clear anything blocking the camera, restart and reset Face ID if needed.
iPhone
8 curated resources, easiest first.
Troubleshooting steps for Face ID: update iOS, check settings, clear anything blocking the camera, restart and reset Face ID if needed.
Steps for a device that will not join Wi-Fi, from checking Airplane Mode to resetting network settings as a last resort.
Explains what the cellular status messages mean and how to fix them by toggling Airplane Mode, restarting, contacting the carrier and updating.
Covers common reasons an iOS update fails, such as an unsupported model, low storage or a slow download, and how to retry.
Explains how to force restart an iPhone that will not turn on or is frozen. The button sequence depends on the model.
Troubleshooting for dual SIM setups with an eSIM, including checking plans and the No Service message on the second line during calls.
General checks and separate fixes for when Personal Hotspot will not share the connection over Wi-Fi or USB.
Explains how to use recovery mode and a computer to reinstall iOS when a device will not update or start. Restoring erases data, so try updating first.