Do you have a link to your contact page for me to see? Pasting html code and even shortcodes into the WordPress editor is really really finicky because of the editor and how it functions. Too many times it’s frustrating because it changes code on it’s own and doesn’t always cooperate. One of the issues with tinymce type editors, it rewrites code to what it thinks it should be, even if it’s incorrect. However, let me check out your page and I will take a quick look.