My iPhone autocorrects phrases after they're typed. I cannot turn it off (using the usual).

terriblefate ~ As your iPhone 8 could be almost 8 years old, it's worth checking for a weak, aging battery which can cause various issues. So...

Does your iPhone 8 still have its original battery?

And what's the Maximum Capacity % here?...

Settings > Battery > Battery Health & Charging

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Thank you for replying with your concerns, terriblefate. 😉

Here at the Apple Support Community, we are volunteers (thoughtful Apple users) who share knowledge in an effort to help others, such as yourself.

I understand that you have tried the usual method, so please verify the following:

1. Open Settings
2. Tap General
3. Tap Keyboard
4. Tap or verify that Auto-Correction = Off

If that was the case, then try the following:

Force your iPhone to restart:

1. Press and quickly release the volume up button.
2. Press and quickly release the volume down button.
3. Press and hold the side button until you see the Apple logo (this might take longer than 10 seconds).

If that didn’t help, I am out of ideas at the moment, however; feel free to contact Apple Support for further assistance.

All the best! 👋🏼😉

terriblefate wrote: "...the number you're querying for is 78%..."

terriblefate ~ 78% maximum capacity is not healthy. Apple suggests having the battery replaced at around 80% to ensure the iPhone functions as intended – such as being able to turn off a setting. So consider haiving the weak, aging battery replaced:

iPhone Battery Service

About genuine iPhone batteries

Repair Provider Verification

(Articles found by searching Apple's Knowledge Base.)

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