WebData Distance Based Fee for WooCommerce set up

Hi,

Hope everyone is well. My site is hiremyevent.co.uk I am having an issue setting this plugin up however. I want it to charge 1.50 per mile. However on my checkout page the option does not come up. Here is what I filled in. Any ideas?

https://hiremyevent.co.uk/wp-content/uploads/2021/06/screencapture-hiremyevent-co-uk-wp-admin-options-general-php-2021-06-23-01_30_04-scaled.jpg

Many thanks

The page I need help with: [log in to see the link]