Important Note:
If you are cancelling a label for a courier like Royal Mail or DPD/DPD Local that requires manifests, the label can only be cancelled if the manifest has not yet been submitted containing that label. If you have already manifested the order you will need to contact the courier to cancel it.
Cancelling a Label
Select/tick the order(s) with the label(s) you need to cancel
Click the Ship button to re-enter the shipping interface
Select the Courier so that it matches the courier that the original label was created for
Select any Service from the list of options
Continue to the next page
On the second page you will see the label that has been created and can cancel it from there but clicking the Cancel button. If multiple labels are being cancelled you can click the Cancel All button to do this in bulk
If needed, you can now return to the order and create a new shipping label, or leave the order without a label if necessary.
Here is an example gif for reference using a Royal Mail (OBA) label: