Errors can include
E1000 Description: Unable to generate Royal Mail Label. The Service Level / Service Code combination of "TPN/01" does not exist as a service contract for the Royal Mail Account.
E1000 Description: There is no international destination available for this shipment destination, weight, format and service.
The errors from Royal Mail typically occur when the service selected for the shipment is either invalid or missing from your Royal Mail contract.
To resolve this issue please review the steps below:
Check that you're able to use this service to the requested destination.
Verify that the service is on your Royal Mail contract or account.
Ensure that you've selected the correct service for the order contents.
If you've used this service before, your Royal Mail contract may have changed, or the courier service may not be set up correctly in accordance with your Royal Mail contract.
Contact Royal Mail to check if there's an issue with your contract or service setup.
If Royal Mail confirms there's no issue but you're still unable to generate labels, raise a new case online and reference the title of this article.
By following these steps, you should be able to resolve the error.