Hi. I actually just copied the text of an original post from 2020 (https://discussions.apple.com/thread/252114319) because it has still never been resolved. There are entire Reddit subs dedicated to this conversation. So it isn’t just a one time thing and it isn’t just me.
For instance, when I’m on my iPad and I swipe to spell my name, it types this: Patricia’s. Every single time. For a couple years now. I have reset my keyboard settings, even reset my iPad to factory fresh and done all the other things suggested in the original post, but it does nothing. Then I googled further and it is suggested that nothing can be done about this at all. It’s just something to live with.
So I had to create a workaround. I created a shortcut so that when I type “Patr” it completes my name without the addition of an apostrophe S. There are several words that I’ve had to make shortcuts for just because of this. It doesn’t sound like a big deal, but it’s especially annoying when you’re typing along by swiping, but you have to remember to pause on certain words. It makes no sense.