My wife has a Samsung Galaxy S8+ with Oreo. Often when I send her a text containing an emoji, or she sends me one, the other person receives it as a box like this: ☒
I have a Nokia 6.1. But my suspicion is that her phone, not mine, is the problem, because I saw the same thing when I had a Windows phone.
What do I need to do to her phone to get it to send emojis properly?