Checkout - Billing Address Error

Object Reference not set to an instance of an object error faced on Step 1 or 2.

On Step 1, Billing address ticked same as shipping address, if ticked I get an error when clicking continue.

If unticked on Step 1, on Step 2 I get the same error when selected shipping address from dropdown and clicking continue.

Was unable to complete Checkout.

Nice catch! Turns out there was a bug in our loader that wasn't adding the warehouse to some of the products. Failure happened during checkout when the store asked the product where it was shipping from. Turns out you can't ship from nowhere 🙈