Hello Odoo experts,

I'm creating sales orders with the JSONRPC API of Odoo. 
I recently noticed that the delivery zone was not being properly determined, so I assumed I had to add the field to my request. The problem is that is not working, the value I'm passing is not being considered.

Any idea why?

This is the body of my request:
{ "method": "call",
"params": { 
​ "service": "object", 
​ "method": "execute_kw",
​ "args": [
​ ​ "x",
​ ​ "y", 
​ ​ "z", 
​​"sale.order", 
​ ​ "create", [
​ ​ ​ { "warehouse_id": 1,
​ ​ ​ "partner_id": 44720, 
​ ​ ​ "partner_invoice_id": 44722, 
​ ​ ​ "partner_shipping_id": 44728, 
  ​ ​  ​"date_order": "2024-05-21",
  ​ ​ ​ "validity_date": "2024-05-21",
  ​ ​ ​ "referencia_pedido_choco": "test", 
  ​ ​ ​ "user_id": 16,
  ​ ​ ​ "type_id": 3,
  ​ ​ ​ "state": "to_approve",
  ​ ​ ​ "commitment_date": "2024-05-22 08:00:00",
  ​ ​ ​ "payment_mode_id": 12, 
  ​ ​ ​ "payment_term_id": 12, 
​ ​ ​ "imprimir_factura": true,
​ ​ ​ "delivery_zone_id": 21, 
  ​ ​ ​ "valued": true, 
​ ​ ​ "pricelist_id": 1, 
​ ​ ​ "order_line": [ [ 0, 0, { "product_id": 13972, "product_uom_qty": 2 } ] ] } ] ] }}