Upgrade my iPhone
How can I upgrade my iPhone 6plus iOS 12 to latest version
iPhone 6 Plus, iOS 12
Question marked as
Hello,
An iPhone 6 (or 6 Plus) will only update as far as iOS 12.5.7. To ensure you have at least that, you can try updating your device. When updating, your device will update to the highest version currently available that it will support, or it will just say it is up to date and won't offer to install anything. If you want to run a higher system version than your current device will support, you need to buy a newer device.
This support article has instructions about updating your iPhone or iPad wirelessly --> Update your iPhone or iPad - Apple Support
You can also use Mac and PC computers to update system software: Update iOS on iPhone - Apple Support
Even though your profile information says you are running iOS 12, I do not automatically assume it is fully updated to the current version.