The billing information for the invoice recipient.
phoneobject<phone>Optionaladdressobject<address>Optionalcountry_codestringRequiredNote: The country code for Great Britain is `GB` and not `UK` as is used in that country's top-level domain names. Use the `C2` country code for China worldwide for comparable uncontrolled price (CUP) method, bank card, and cross-border transactions.
statestringOptionallanguageenumOptional