Why does my API Post fail while Get works in Postman?

[Fromm60056]

I am simply using Postman to do APIs. I am able to to a GET for an order, but when I try to POST,(close.json) it fails, the response is useless, so I do not know why it fails. Can anyone help? 

[gsmaverick]

Can you share more details on the request you're making and the response you got back?

[Fromm60056]

I can GET orders without issue and the order I have retrieved is correct in the URL:

admin/api/2023-07/orders/5131391369383/fulfillment.json

{

    "errors": "Not Found"

}

So, I have no ide what is not found or why.  Who creates the fulfillment #? Shopify or the outside app?