create-a-purchase-receive API issues

Hello all,

I'm trying to use the create a purchase receive inventory API documented here (https://www.zoho.com/inventory/api/v1/purchasereceives/#create-a-purchase-receive) however when I do am getting the following error

{"code":9,"message":"The purchase receive should be associated with a purchase order"}

The documentation doesn't mention anything about a required field to associate a Purchase order. That said, I have tried including both the "purchaseorder_id" and "purchaseorder_number" key and value in the API call with no luck. Does anyone know how to get past this error?