Hello Debbie

Issues like this usually occur when there is a conflict either with the theme currently active on your website, or another plugin you have installed.

In this case, I believe the theme is adding some CSS to the button, which makes it invisible until you hover over it. Here it is:

So, when I disable this background-color property when I inspect the page, the button appears normally.

Good work, Debbie.

Thanks for letting me know.

You could also find that selector, copy it and define the color, and include it as HTML above Amelia's shortcode, like this:

<style>
 button#am-continue-button {
    background-color: white !important;
 }
</style>

And it should look like this:

If you get it to work like that, you can revert the color of the text.

You're welcome, Debbie

Glad I could help.