Fatal Error Loading Plugin

Hey Dave,

I am getting an error loading the super speedy sales page plugin. I have attached an image, but the error is:

Fatal error: Cannot declare class Woocommerce_onsale_page, because the name is already in use in /sites/hightide/public_html/wp-content/plugins/super-speedy-sale-page-woocommerce/includes/class-woocommerce-onsale-page.php on line 30

How Can I resolve this?