1. Make sure you marked products as FFL required in the product edit view. If you have FFL Cockpit, this step is automated and all firearms should be already marked as FFL Required.
2. Make sure you have a Shipping Zone defined under WooCommerce –>Settings–> Shipping Tab
3. Then make sure you have settings that looks ike this, making sure the Default to customer shipping address is selected.

If those don’t work, and you have a newer install of WordPress, continue below….

Since WooCommerce 8.4, the management of cart and checkout pages has shifted to blocks, by default. What this means is that certain plugins including Checkout right now are not compatible with the Blocks format. There is a way to fix this though, until we make the plugins compatible:

Steps to Resolve:

• Using a block theme: Go to Appearance -> Editor -> Pages -> Select Cart or Checkout -> click the Edit icon
  Using a non-block theme: Go to Pages -> All Pages, and then locate and edit the Cart/Checkout page.
• Open the List View and select the Cart or Checkout block.
  If you have an incompatible extension installed, a notice will be displayed and you can revert in 1 click.
• Open the Block Transform menu as seen in screenshot below.
• Choose “Classic Shortcode”.
• The block will be transformed into a Classic Shortcode placeholder block.
• Save your changes by clicking the Update button in the top bar.