Facing issues in iOS 8.4.1

Howdy z.ehsan,

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The troubleshooting tips in the article below may help you resolve the issue with the flash on your iPhone 5s.

Get help with the camera on your iPhone, iPad, or iPod touch - Apple Support

Your flash isn't working

If the flash isn’t working, or if it’s going off every time you take a photo, check your flash settings. Tap the lightning bolt in the upper left of the screen to choose a different setting.

If you take extended video with the flash on, or you’re using the device in a very warm environment, you might see (disabled flash icon). You won’t be able to use the flash until your device cools down.

If the flash is on when you’re not using the camera, check the Control Center to see if the flashlight is on.

So long.