We have an user saying that activating our app breaks the “Address verification system”, they want to “Require shipping and billing address to match”, and it seems that either our payment function or adding an attribute to the cart breaks it.
The checkout is supposed to only have the “Shipping address” field once you’ve selected that option, but it seems to add the “Billing address” form as well once you activate our app:
We’ve tested from our side and were able to replicate the behavior.
If you need more info please send me a inbox message because we’d like to not publicly reveal information about the user and store.
Hi @David_Arbias, which operations is your Payment Customization Function using? I’ve tried hide, move, and rename operations with cart attribute changes via a Checkout UI Extension on a test shop and wasn’t able to replicate this.
I’ll send you a DM to gather some more details so we can dig into this.
I reviewed our logs to investigate this issue and found the root cause:
The “require shipping and billing address to match” checkout setting only applies when the selected payment method is credit card, offsite payment extension, or Cash on Delivery. For alternative payment methods, the billing address section is always shown regardless of that setting.
Your payment customization is hiding the credit card based on the cart attribute, which leaves only alternative payment methods available. That’s why the billing address section appears.
Thanks, this seems to be a missing feature in Shopify.
I’ve submitted a feature request so we can explore adding this 
