should pass it as additional field. For example: <code>{"name": "promocode", "value": "some code", "type": "text"}</code>See [[#book response|example]] of <code>book</code> API method response. | should pass it as additional field. For example: <code>{"name": "promocode", "value": "some code", "type": "text"}</code>See [[#book response|example]] of <code>book</code> API method response. |