> 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/grp-returns-api/error-handling/api-specific-error-codes.md).

# API Specific Error Codes

The following table lists the unique error responses for both versions of the Returns API.

### GetReturn

| Code | Message                              | Description                                                 |
| ---- | ------------------------------------ | ----------------------------------------------------------- |
| 0    | RequestDoesNotContainAllRequiredInfo | A required field is missing.                                |
| 2    | ReturnOrderNotFound                  | The system could not find the return order in the database. |

### UpdateReturn

| Code | Message                                            | Description                                                                      |
| ---- | -------------------------------------------------- | -------------------------------------------------------------------------------- |
| 0    | RequestDoesNotContainAllRequiredInfo               | A required field is missing.                                                     |
| 1    | ReturnOrderNotFound                                | The system could not find the return order in the database.                      |
| 2    | ReturnOrderNotUpdatedReturnIsAlreadyOnHold         | The return order is on hold.                                                     |
| 3    | ReturnOrderNotUpdatedReturnOrderWasNotOnHold       | The return order is not on hold.                                                 |
| 4    | ReturnOrderNotUpdatedOrderArticlesDoNotMatch       | The order articles in the request do not match the articles in the return order. |
| 5    | ReturnOrderNotUpdatedReturnHasAlreadyBeenProcessed | The return has already been processed.                                           |
| 7    | ReturnOrderNotUpdatedReturnHasAlreadyHadActivity   | The return order had an activity, for example, the status was changed.           |
| 8    | ReturnOrderNotUpdatedReturnHasAlreadyBeenCancelled | The return order is already cancelled.                                           |

### CreateReturn

| Code | Message                                             | Description                                                                                               |
| ---- | --------------------------------------------------- | --------------------------------------------------------------------------------------------------------- |
| 0    | RequestDoesNotContainAllRequiredInfo                | A required field is missing.                                                                              |
| 1    | OrderNotFound                                       | The system could not find the order in the database.                                                      |
| 2    | ReturnOrderNotCreatedCancelOrderIsNotAllowed        | The return order could not be created because the order cancellation is not allowed.                      |
| 3    | ReturnOrderNotCreatedCancelOrderIsNotValidForReturn | The return order could not be created because the matching order articles are not available for a return. |
| 6    | ReturnOrderNotCreatedLabelFailed                    | The return label could not be generated.                                                                  |

### UndeliverableReturns

| Code | Message                                           | Description                                    |
| ---- | ------------------------------------------------- | ---------------------------------------------- |
| 0    | RequestDoesNotContainAllRequiredInfo              | A required field is missing.                   |
| 1    | PackageNotFound                                   | The system is unable to find the package.      |
| 2    | PackageItemHasAlreadyBeenProcessedAsUndeliverable | An undeliverable return order already exists.  |
| 3    | AtleastOnePackageItemHasAlreadyBeenReturned       | The order articles have already been returned. |


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