[Klarna] Why does a Checkout v2 «order» request fail with the message «"Bad format: 'reference' is not part of the schema"» when a «reference» for a «shipping_address» object is specified?

Extensions Klarna
, ,
1 
{
	<...>
    "shipping_address": {
        "family_name": "Fedyuk",
        "given_name": "Dmitry",
        "reference": ""
    }
	<...>
}

The Klarna’s server responds:

Bad format: ‘reference’ is not part of the schema

The «reference» field is described in the Klarna documentation:

2

See also: