Here are some solutions for flashlight iphone not working
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If you have a cover on your phone, first take it off.
Next, turn off the low power mode.
Keep your phone charged.
Check the LED flash for notifications.
Check to see whether your iPhone isn't extremely hot or chilly.
Turn off the light.
Tap Forced App Closing.
Upgrade to iOS 11 as soon as possible. Force your iPhone to restart.
Reset all of the settings
Revert iOS 16 to an earlier version.
Reset your iPhone to its default settings.
Contact Apple Support now.