REST Admin API, about province_code

[APIDev]

Please (TT)

In the REST Admin API, pass the value of
as "shipping_address" property
-"province_code" as "JP-03"
-"province" as "岩手県".

But, it is not reflected correctly at checkout.
province_code = null
province = null

I already checked the official documentation.

reference
about order Json

https://shopify.dev/docs/api/liquid/objects/order
about address OBJ
https://shopify.dev/docs/api/liquid/objects/address

[APIDev · Accepted solution]

The problem self-resolved.

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