Is there anybody that uses this update

Update your iPhone by following these instructions:

Update your iPhone or iPad - Apple Support

Note you can only update an iPhone 6s to iOS 15, the latest version of which as I wrote this is iOS 15.7.3

The iPhone 6s hardware cannot run iOS 16.

Use a computer or the Software Update function in Settings. If it's on 12.4.2 through 12.5.7, it's not an iPhone 6s and isn't capable of 13 or above; if you encounter another specific issue, describe it in this thread.

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