As of 6 December 2019 a new handling result (FAILED_TO_CREATE_SHIPPING_LABEL) will be added to the returns domain and can be returned from the return endpoints on the API as of then. This new handling result indicates that the transporter failed to create the shipping label and that the return is cancelled. The customer has to announce his/her return again before sending it back to you.
Please be aware that you can receive this handling result as of this date through the returns endpoint at https://api.bol.com/retailer/public/redoc/v3#operation/get-return. Find all the available handling results at our functional documentation via https://developers.bol.com/apiv3returns.
Example code snippet