How do I update my iPhone 6s Plus?

firoj273 wrote:

I phone updated

Probably

[Edited by Moderator]

Assuming you have a compatible device, see: Update your iPhone, iPad, or iPod touch - Apple Support

And: If your iPhone, iPad, or iPod touch won't update - Apple Support If the above Apple articles do not help, please post back with relevant information. 

The latest version of iOS that iPhone 6s can run is iOS 15.8.3, if you already have that and you are looking to update to iOS 16,17, or 18 then your iPhone is not compatible with those versions of iOS. Hope that helps.