Not Found message when I am trying to use fullfillment service. (Urgent)

[aydinbahar]

Not Found message when I am trying to use fullfillment service. I am using ShopifySharp library with below request.

{
"created_at":null,
"line_items":null,
"order_id":1004,
"receipt":null,
"status":null,
"location_id":60987113726,
"email":null,
"notify_customer":false,
"destination":null,
"tracking_company":"DPD",
"tracking_number":"01745434521549",
"tracking_numbers":null,
"tracking_url":"https://tracking.dpd.de/status/en_EN/parcel/DPD01745434521549",
"tracking_urls":null,
"updated_at":null,
"variant_inventory_management":null,
"service":null,
"shipment_status":null,
"name":null,
"id":null,
"admin_graphql_api_id":null
}