dodomiz on "[Plugin: WooCommerce - excelling eCommerce] Action failed. Please refresh the page and retry."

hi,
i'm getting this Message "Action failed. Please refresh the page and retry." every time i'm push the button "Make a Reservation".
i tried everything that i found in the forum and nothing worked it up.
i need your help to resolve this issue. please help :)

http://wordpress.org/plugins/woocommerce/