HTML Buy Button

I’m trying to add Buy Now code to my WordPress site at https://www.dreamwyndpublishing.com/buy-your-book/ I’ve copied the code exactly as it shows at PayLoadz. But when I paste it into my page no button is generated. It just stays as code. Never had this problem with my HTML built sites. Nor do I recall a problem with it on earlier versions of WP and other themes. I tried the code out on a site running Weaver II Pro and got the same result. Yet, I’m pretty sure my code worked with Weaver before.

I am using the Twenty Sixteen theme this time on WordPress 4.4.

I was testing out the Easy Digital Downloads, but can’t quite figure it out. I’ve had a PayLoadz account for years, but thought I’d try something new. But it’s much easier to just keep with PayLoadz . . . if I could get the code to work.

Looking forward to some knowledgeable soul to help me out!