Error 400: Unable to save shipping information. Please check input data.
Here we can look on another weird thing - why right now we are using another address attribute name asi it is on customers/me calls? For example on customers/me call
region is array, customer_id vs customerId, region_id vs regionId, country_id vs countryId... The right hand does not know what makes left...
So how we can set saved address to cart? We cant... What we need to do is to get address from customers/me, then rewrite it to different structure in shipping-information call AND delete address ID. So call should look like