Object reference Error when creating order using api

Hello, about a week ago I was able to create orders using apis just fine using the steps mentioned here: https://web.archive.org/web/20220318194607/https://developers.vtex.com/vtex-rest-api/docs/using-apis-to-place-a-regular-order

Now I get “Object reference not set to an instance of an object” on step 4. Place the order.

Seems like there was an update on the apis used, but I’m jot seeing changes in the documentation so I can fix the issue.

Any help is appreciated, thanks and have a good day.