> For the complete documentation index, see [llms.txt](https://developer.esw.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.esw.com/returns-api/returns-api-v2.1/methods/create-an-undeliverable-return-order.md).

# Create An Undeliverable Return Order

To create a return order for an order or package that could not be delivered to the shopper, send a `POST` request to `/api/v2.1/UndeliverableReturns`.

<details>

<summary>Required Parameters</summary>

| **Parameter**      | **Type** | **Description**                                                                                                                                                                                                                                   |
| ------------------ | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| brandCode          | String   | <p>ESW’s unique identifier for the retailer.</p><p>Example: <code>GOC</code></p>                                                                                                                                                                  |
| packageReference   | String   | <p>The retailer's unique reference number for a package.</p><p>Example: <code>123456789A</code></p><p>Do not use special characters like <code>#</code>.</p><p>Not recommended: <code>AAA#1234</code></p><p>Recommended: <code>AAA1234</code></p> |
| emailAddress       | String   | <p>The email address of the shopper.</p><p>Example: <code><jane@janedoe.com></code></p>                                                                                                                                                           |
| requestUpdateLabel | Boolean  | Indicates if a label should be returned in the response. The values are `true` or `false`.                                                                                                                                                        |

</details>

### Response <a href="#response" id="response"></a>

When you send the API request, the system validates the request parameters and searches for the order/package in the ESW database. The system also ensures that an undeliverable return order does not already exist for the same package.

<details>

<summary><strong>HTTP Response Status</strong></summary>

| **Response Code**     | **Description**                                                                                                                                                                                                                                                                                                                                                                                                                      |
| --------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| **201 - Created**     | <p>Indicates that an undeliverable return is created. Additionally:</p><ul><li>Each order article in the order is marked as Returned with the reason code as <code>CancelRuleInvoked</code> and linked to the return.</li><li>The event is created and assigned to the return in the database.</li><li>If the <code>"requestUpdateLabel": "true"</code> in the API request, the updated label is returned in the response.</li></ul> |
| **400 - Bad Request** | Indicates that the request does not contain the required details.                                                                                                                                                                                                                                                                                                                                                                    |
| **404 - Not Found**   | Indicates that the package could not be found. If any of the return order articles have already been returned previously, the API returns a response indicating that an undeliverable return order already exists.                                                                                                                                                                                                                   |

</details>

### Request Example <a href="#request-example" id="request-example"></a>

The following example shows how to create a return for an undeliverable order and get a returns label in the response.

<details>

<summary>Request body</summary>

{% code expandable="true" %}

```json
{
  "brandCode": "ABC",
  "packageReference": "123456789A",
  "emailAddress": "test@example.com",
  "requestUpdateLabel": true
}
```

{% endcode %}

</details>

### Response Example <a href="#response-example" id="response-example"></a>

<details>

<summary>Response body</summary>

{% code expandable="true" %}

```json
{
  "responseCode": 1,
  "responseMessage": "",
  "emailAddress": "test@example.com",
  "updateReturnLabel": "VGhpcyBpcyBhIHRlc3QgbGFiZWwgd2l0aCBub3RoaW5nIGluIGl0IGFzIGl0IGlzIGp1c3QgZm9yIGFuIGV4YW1wbGU="
}
```

{% endcode %}

</details>


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