Begin by selecting the "Inventory" button from the menu at the left of the page.

Next, Filter your Inventory for Delivery Logistics and search for your "Standard Delivery," then click on the three dots (. . .) to bring up options to edit. From the dropdown menu, select "Edit Service".

Finally, scroll down until "Mileage Rate" appears in view. Edit the cost per mile to suit your needs.
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Don't forget to "Save & Close" before exiting.
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