The above error may occur when creating Royal Mail labels for the following reasons.
1. You are trying to use a delivery service that was not requested when you first set up your account. Please reach out to support and we can add any additional services for you.
2. There are no barcodes remaining on your account. In this scenario. Please reach out to support and we can replenish your barcode ranges for you.
If you have questions, please contact support.