Shipping cost is the value charged for shipping the products sold. If this amount is already set, it is possible to display it separately from the total purchase amount at the time of payment.

1. Send a POST with the cost and mode attributes of the shipments parameter to the endpoint /checkout/preferences.
2. In cost, enter the freight amount.
3. In mode, enter not_specified.
4. Execute the request.

{
"shipments":{
"cost": 1000,
"mode": "not_specified",
}
}