iOS 11.1.1

The other person's iPhone displays these characters correctly or incorrectly based on whether or not they have the display bug on their iPhone, not based on whether or not you have the display bug on yours. My guess is the other person needs to update iOS on their iPhone.

Samcro13 wrote:

When I try to use certain emojis(mermaid/man) after updating to iOS 11.1.1 there person receiving the text gets the boxes with question marks.

Actually iOS 11.1.1 has nothing to do with what your picture shows. It concerns a bug that occurs when you type the letter "I". The question marks in your picture indicate that the device being used by the recipient does not have a font which supports the latest emoji characters (or for some reason the font is not working). It is something the recipient has to fix.

My bad. I said display issue. Now I remember it's technically a keyboard autocorrect issue. But there's more to it. It's not just incorrectly autocorrecting some characters as you type. It's also autocorrecting them in messages you've received and are displaying in apps in which iOS keyboard is active e.g. Twitter, Messages et c.

Ref. "IPhone “I” Bug: IOS 11 keyboard glitch autocorrects “I” to “A?” and ”#?” — here’s the fix"

Toot Uncommon wrote:

It's also autocorrecting them in messages you've received

That's not right, it can only happen when you type something yourself. If you see it in a received message, it was done by the sender's device.

I agree with Tom

You can check out the picture attached in this post for iOS 11.1.1 update

Have you updated to iOS 11.1.1 yet?

Did the person (your friend) also updated to iOS 11.1.1?