How to create a nested collection in Azure purview through api using postman?

Question

I am trying to create a nested collection in a purview through api using postman. I was able to create a one subcollection under my existing collection in a purview.

Is there a way to create a bunch of subcollections under the existing collection at once?

Data Hierarchy existingCollection > hello > hello-sub

I've tried this as below.

`

{
  "value": [
    {
      "name": "hello",
      "description": "hello description",
      "friendlyName": "hello",
      "parentCollection": {
        "referenceName": "existingCollection"
      }
    },
    {
      "name": "hello-sub",
      "friendlyName": "hello-sub",
      "parentCollection": {
        "referenceName": "hello"
      }
    }
  ]
}

`

When I checked the purview, there is one hello collection created outside of exsitingCollection. I don't see hello-sub collection at all.

Can anyone help me create a nested collection under my existing collection in a purview please?

Thank you in advance!!!