Some selling channel integrations create the shipping label for your orders before you import them into ShipStation. In these cases, ShipStation prevents you from altering certain order details. This is to ensure the shipment details in ShipStation match your label and order source at all times.
These restrictions currently apply to the following selling channel integrations (more to come soon!):
Mercado Libre (for US-based merchants)
Since a label is already created for these orders, the following actions are not permitted:
You cannot edit order summary or recipient details.
You cannot change the shipment configuration - weight, service, package type, etc - for the orders (these options will not be present for these orders in ShipStation).
You cannot void labels for these orders in ShipStation.