Am I installing this plugin right?

We are trying to install this plugin
on this web page http://www.aippolygraph.org/directorio/
but all I am getting is a whatsapp button that is different
to the picture shown on this page https://wordpress.org/plugins/whatshelp-chat-button/

So I am wondering if I am doing something wrong