Issue adding a Vendor Bill using the SuiteTalk Rest API

I am trying to use the Netsuite SuiteTalk Rest API to create a Vendor Bill but I keep running into the same error “Error while accessing resource: Please enter value(s) for: Branch Location”. I checked that I do have the “Branch Locations” permission and have tried several formats for the location tag but I still get the same error. Below is an example of the JSON i am trying to send.

{
    "entity": { "id": 3214 },
    "TranId": "3442242",
    "item": {
        "items": [
            {
              "item": { "id":"123" },
    	      "itemType": "InvtPart",
              "description": "Example Item Description",  
    	      "location": { "id":"456" }, 
              "quantity": 3, 
              "rate": 0.74,
	      "line": 1,
	      "amount": 2.22
            }
        ]
    }
}

I am able to list the locations using the API. I have also tried using “location”: “456” and “location”: 456 but those do not work either.

Any help would be greatly appreciated this one has me really stuck