You can only generate one label with the same Shipper Reference.
If you are trying to generate your labels but you can't due to "This Shipper Reference already exists" error verify that the order doesn't present a Shipper Reference previously employed. 🗳
If that were the case, Carrier's Server has already registered a shipment with that Order Reference and it won't accept a new transmission with an identical one.
What can I do to solve the issue? 🔎
We suggest to make a first attempt trying to change the preference from My Profile > Preferences > Order reference printed on the labels. Switch from ShippyPro order number to Marketplace order number or vice versa.
Then, save the settings at the bottom of the page and come back to Shipping Labels section to correct the order.
📌In this way you should be able to evade the system by sending a new Order Reference that is different from the previous one.
If the error persist, you need to create a new label as Manual Shipment.