Create multi row EFF using Item REST API V2

Summary:

Hi,

I am trying to create Item with multi row WFF using REST API ItemV2.

I am able to create 1 row in multi row EFF but now how to create multiple rows at the time of item creation using REST.

Content (please ensure you mask any confidential information):

Payload-

{
"OrganizationCode": "000",
"ItemClass": "XXXX",
"ItemNumber": "RACK-3",
"ItemDescription": "Rack-1",
"PrimaryUOMValue": "EA",
"UserItemTypeValue": "Finished Good",
"ItemStatusValue": "Active",
"LifecyclePhaseValue": "Production",
"Template": "XXXX",
"ListPrice": 123,
"DimensionUOMValue": "CM",
"WeightUOMValue": "KG",
"UnitWeightQuantity": 123,
"UnitWidthQuantity": 123,
"UnitLengthQuantity": 123,
"UnitHeightQuantity": 123,
"ItemEffCategory": [
{
"CategoryCode": "****",
"SalesGroup": [
{
"salesPricingGroup": "****"
}
],
"MarketabilityByEntity": [
{
"marketabilityByEntity": "I31"
}
]
}
],
"ItemCategory": [
{
"ItemCatalog": "XXXIntrastat Catalog",
"CategoryName": "XXXX"
},
{
"ItemCatalog": "XXXX Purchasing Catalog",
"CategoryName": "XXXX"
},
{
"ItemCatalog": "**** Commercial Catalog",
"CategoryName": "XXXX"