once shipping address is edited, it remains billing address

[Guest]

Where would I look to see what's causing this?

 

Basically, the customer enters their billing info on create_account.php

Once they get to checkout_confirmation.php they decide they want it shipped to a po box or something

They create & save that new address. checkout_confirmation.php reflects the appropriate changes.

 

customer gets an email with their changes.

when i view their order in admin, the billing address is the shipping address, and the same is said for their account_history page.