Failed to generate label: shipment.References:The billing preference DPT is missing or its value is invalid. 'id' cannot be null. [Solution]

When processing an order, you might run into the "Failed to generate label: shipment.References:The billing preference DPT is missing or its value is invalid. 'id' cannot be null." error.

This error relates to a misconfiguration of the Billing Account of the Client you're trying to process the order for.

Feel free to follow the step-by-step guide written below or the video guide, as you prefer:

To solve this issue you will have to:

1. Access Clients under the Maintenance menu
   
   
   
   
2. Click on the client related to the order
   
   
3. Edit the Billing Account (Carrier) related to the order and error
   
   
   
4. Select the Carrier Options tab
   
   
5. Select the reference you want to use in the DPT Reference dropdown or type in a fixed reference
   
   
6. Press Save to apply the changes
   
   
   

If the rest of the order information is correct, you will be able to Process or Process and Print.