Unable to update my iPhone 6 Plus

Apple released the iPhone 6 Plus about ten and a half years ago, in September 2014. You can update an iPhone 6 Plus to the latest release of iOS 12 – currently iOS 12.5.7. You cannot update an iPhone 6 Plus to iOS 13 or higher, and many app vendors have abandoned iOS 12 and the iPhone 6. Some apps now require a minimum of iOS 16, or even a minimum of iOS 17 (e.g., UPI payment apps in India).

If you need to run modern apps, it is time to buy a new iPhone, preferably an iPhone 15- or 16-series phone that can run iOS 18 and that is likely to receive several years' worth of future updates. In some countries and regions, Apple sells Certified Refurbished iPhones through their online store. These have a new battery, new outer shell, and a one year warranty, unlike "refurbished" or "renewed" phones you might see some third-party vendors selling.

iPhone - Apple

Buy iPhone - Apple

Refurbished iPhone Deals - Apple

The All Too Common SAD Reality of Buying a Used iPad/iPhone – Apple Community

Use Quick Start to transfer data to a new iPhone or iPad - Apple Support

What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support

That is correct. Your iPhone 6 Plus is over 11 years old and has long stopped receiving the latest iOS updates. As a result, it cannot go past iOS 12.5.7.

An iPhone 5s, iPhone 6, or iPhone 6 Plus isn't capable of 13 or above; they require at least 2GB of RAM. If you're trying to install 12.5.7, describe what happens.

(260041)