POST - create test script: step by step issue

Hello,

I am using Zephyr Scale Cloud and encountering an issue when editing test steps.

I am successfully able to:

Create a new test case using POST /v2/testcases with the following JSON:

{
"projectKey": "DZIA",
"name": "Login Test"
}

Edit steps for plain text scripts using:

POST /v2/testcases/DZIA-T176/testscript

{
"type": "plain",
"text": "e.g. Attempt to login to the application"
}

However, I am unable to update test steps one by one (step-by-step) as described in the documentation.

The documentation states: To define your own test steps, use the POST /testcases/{testCaseKey}/teststeps endpoint after creation using OVERWRITE mode AND For Plain Text scripts, we support HTML fragments. To create a step-by-step test script, you should use the POST /testcases/{testCaseKey}/teststeps endpoint.

POST /v2/testcases/{testCaseKey}/teststeps?mode=OVERWRITE
with a JSON body:

[
{
"description": "Your step description",
"expectedResult": "What you expect after the step"
},
{
"description": "Next step description",
"expectedResult": "Next expected result"
}
]

…but this request does not work.

Response:
{
"errorCode": 400,
"message": "Invalid Payload"
}

Questions:

Is the provided JSON structure correct for importing step-by-step instructions?
Could you provide an explicit example (expected JSON payload) for step-by-step test steps?

Thank you guys!