Unable to update product on ebay using API (404 not found), but fetch works

[originsnyc]

When we try to get inventory Item using API in production ebay

GET https://api.ebay.com/sell/inventory/v1/inventory_item/bc05ace5-50cb-4c4e-b516-3afb10f87eda

Response

{
  "sku": "bc05ace5-50cb-4c4e-b516-3afb10f87eda",
  "locale": "en_US",
  "product": {
    "title": "Marni Black Daisy Hooded Sweatshirt Gold",
    "aspects": {
      "Size": [
        "48"
      ]
    },
    "description": "Marni Black Daisy Hooded Sweatshirt Gold",
    "brand": "Marni",
    "mpn": "MBDHSG"
  },
  "condition": "NEW",
  "packageWeightAndSize": {
    "packageType": "USPS_LARGE_PACK",
    "weight": {
      "value": 5,
      "unit": "POUND"
    }
  },
  "availability": {
    "shipToLocationAvailability": {
      "quantity": 0,
      "allocationByFormat": {
        "auction": 0,
        "fixedPrice": 0
      }
    }
  }
}

Now when I update this inventory item with same body as above, I get below response

PUT https://api.ebay.com/sell/inventory/v1/inventory_item/bc05ace5-50cb-4c4e-b516-3afb10f87eda

{
  "errors": [
    {
      "errorId": 25710,
      "domain": "API_INVENTORY",
      "subdomain": "Selling",
      "category": "REQUEST",
      "message": "We didn't find the resource/entity you are requesting. Please verify the request"
    }
  ]
}

 This does not make sense as inventory item is available in ebay. Kindly help