software update
I’m aware there is a new update however my phone is currently on iOS 12.4.8 and says its up to date and therefore isn’t giving me the option to update it to the newest version of iOS
iPhone 6s Plus, iOS 11
An unit running 12.4.8 doesn't have enough RAM to run 13 or above. It also won't be the iPhone 6s Plus listed below your post.
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