Our Shopify storefront is fulfilled by Amazon (FBA - Fulflilment By Amazon). For orders placed directly via the Shopify storefront, these orders are being fulfilled properly by FBA.
However, for Draft Orders, which are being sent and completed by an external system, despite being properly completed for fulfillment, are not being fulfilled by FBA. Instead, the status is "Fulfilled by Shopify".
Per discussion with Shopify support, we've tried various values in the "fulfillment_service" field of either "amazon" or "amazon_marketplace_web". These were literal values suggested by Shopify support.
However, neither of those values properly invokes the FBA.
Does anyoine have any experience or suggestions?
Thanks in advance.
I've seen draft orders fail if you don't choose a shipping method, or if the shipping method doesn't match exactly the Amazon names (Standard Shipping, Expedited Shipping, etc).