Update downloading
My phone can not download updates
iPhone 6s Plus, iOS 14
Question marked as
Top-ranking reply
Look first if this help.
You can update the iPhone 6S Plus to iOS 15, see this Apple article: iPhone models compatible with iOS 15
https://support.apple.com/en-gb/guide/iphone/iphe3fa5df43/ios
At the top left you can select the correct iOS.
On the iPhone: Go to: Settings -> General -> Software Update