How to update IOS 15.6

If your iPhone is eligible for an update, you can check by reading this Apple article:

iPhone models compatible with iOS 15.6.1

iPhone models compatible with iOS 15.5 – Apple Support (UK)

Then go to: Settings -> General -> Software Update

See the following Apple articles:

Update your iPhone, iPad, or iPod touch

Update your iPhone, iPad, or iPod touch - Apple Support (IN)

If your iPhone, iPad or iPod touch won’t update

If your iPhone, iPad, or iPod touch won't update - Apple Support

You can do the update via PC, see this Apple article: Update software on iPhone, iPad or iPod touch in iTunes on PC

Update software on iPhone, iPad or iPod touch in iTunes on PC – Apple Support (UK)

If you have a Mac see this Apple article: Update your iPhone, iPad, or iPod touch with the Finder

Update your iPhone, iPad, or iPod touch with the Finder - Apple Support

You need about 7 GB device storage and good Service & Wi-Fi.

If they are On, turn Off Hotspot & VPN.

If you aren't seeing the option to update and you are running iOS 12.5.5, you don't have an iPhone 6s. You have an iPhone 6.

Otherwise:

Update iOS on iPhone - Apple Support

Use a computer or the Software Update function in Settings. If you encounter a specific issue, describe it in this thread.

It'll install 15.6.1. It's no longer possible to update to exactly 15.6.

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