curl --request PUT \
  --url https://api.meetcampfire.com/rr/api/v1/contracts/{contract_id}/subscriptions/{subscription_id}/allocations \
  --header 'Authorization: <api-key>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "lines": [
    {
      "product": 123,
      "amount": 0
    }
  ]
}
'

{
  "id": 123,
  "source_bundle": 123,
  "source_bundle_name": "<string>",
  "total_amount": 0,
  "currency": "<string>",
  "lines": [
    {
      "id": 123,
      "product": 123,
      "product_name": "<string>",
      "product_id_str": "<string>",
      "amount": 0,
      "percentage": "<string>",
      "original_percentage": 0
    }
  ],
  "created_at": "2023-11-07T05:31:56Z",
  "last_modified_at": "2023-11-07T05:31:56Z"
}