Emoji Mystery. Some work, Most don’t show up.

For some reason recently, emojis are not working properly. I am using standard Apple emojis. A few emojis work but most don’t appear in my post when I publish. I can add them to the post but as soon as I publish the post they disappear. I added some random emojis right after the title to show you what I mean. I am including a screenshot of the ones I added so you can compare it with the published link at the bottom of the article under the references. When you click the link you will see that most emojis have disappeared and only a few were published.Any idea how to fix this emoji problem?

The page I need help with: [log in to see the link]