If fulfillment has already been "Requested" for the order, then you will need to contact the supplier to cancel and refund the order.
This is to protect suppliers from having their orders canceled mid-fulfillment without warning.
If fulfillment has not been requested for the order, you can cancel the order and refund the customer as you would with any normal Shopify order.
Don't know how to correctly process a Carro refund? Please refer to this article.
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