Why is my new API fulfillment creation not working?

Technical Q&A
1

https://help.shopify.com/en/api/guides/managing-fulfillments#create-a-fulfillment
I follow tutorial above step by step, and the post json format is:

{
    "fulfillment": {
        "location_id": 123456789,
        "tracking_number": "123"
    },
    "line_items": [
        {
            "id": 87654321
        }
    ]
}

if the operation success, I should get a response with status code 201-created, but what I got is 200-OK with response body

<html>
    <body>
        <noscript>
            <a href="https://app.shopify.com/services/login/identity?destination_uuid=f64f861e-1f2b-41fa-a36b-ba8f0c1e4e9b&return_to=https%3A%2F%2Fapp.shopify.com%2Fservices%2Flogin%2Fidentity_callback%3Fshop_name%3DLiving%2BMenu%26state%3DXoH1z8Y9-EVEIZEKSd7hHBOGhZE_e4rSWK_W2DLl-EEz399a2wFmYugpnUSzGH1KJDR7a2pVyZ-q18uBzdbNDmGyGddgtf8SAeQ5b_klSTgeza1jDAtOkhl1rAM6F4CmuLhkHXWubNzSu97IjMLl8_gKV1zR3_rYKf_Lv8EHTlMJMqRtaIZqnmuB-OpR0Y4BfnGticd3Ly3LwOOwpSUQCIsFIduPACGNcYS4zbPqLpU%253D&ui_locales=en&upgradeable=false&ux=shop">Continue</a>
        </noscript>
        <script type="text/javascript">
      window.location = "https:\/\/app.shopify.com\/services\/login\/identity?destination_uuid=f64f861e-1f2b-41fa-a36b-ba8f0c1e4e9b\u0026return_to=https%3A%2F%2Fapp.shopify.com%2Fservices%2Flogin%2Fidentity_callback%3Fshop_name%3DLiving%2BMenu%26state%3DXoH1z8Y9-EVEIZEKSd7hHBOGhZE_e4rSWK_W2DLl-EEz399a2wFmYugpnUSzGH1KJDR7a2pVyZ-q18uBzdbNDmGyGddgtf8SAeQ5b_klSTgeza1jDAtOkhl1rAM6F4CmuLhkHXWubNzSu97IjMLl8_gKV1zR3_rYKf_Lv8EHTlMJMqRtaIZqnmuB-OpR0Y4BfnGticd3Ly3LwOOwpSUQCIsFIduPACGNcYS4zbPqLpU%253D\u0026ui_locales=en\u0026upgradeable=false\u0026ux=shop";
    </script>
    </body>
</html>

I have no idea where did I do wrong, please help!!
Any comment is appreciated

2

I have the same error. Any body there?

3

I have same problem and not able to create fulfillment for any order. anyone can help?