You created a transaction in NAV and noticed the Origin address is being used as the Ship to Address in the Admin Console.
The Shipping Method is set to "Pickup". By using Pickup will send the Origin address/your site address as both the Origin and Destination.
If you don't want the Origin address to be using as the Destination address. Change the Shipping Method to "Delivery". Delivery uses the ship-to address as the address where AvaTax calculates sales taxes.