Embedding Storymap onto Wordpress

I've tried using the embed code provided on my Storymap page to embed the Storymap to Wordpress using custom HTML.

On the editor page, the story map loads and appears as in the photo, just as a box on the page with its own scroll bar. There aren't nay options to make that box fill the page, as I would like. Then when I publish the page, it is gone and the page is completely empty.

Any help with this appreciated!

https://preview.redd.it/m6irqihe507e1.png?width=1919&format=png&auto=webp&s=b1e05ff79e4101f2f39e8d6bf0c2f54f3293bbeb