Prepaid orders are not showing up in Shipstation. Why?
Prepaid orders are a fairly new concept in Shopify, as Shopify introduced them in 2022 in their platform.
We have noticed that some third party apps (Shipstation) still haven't adjusted their systems to the new prepaid orders within Shopify. Their apps still expect to receive a new order in Shopify for each fulfillment even though Shopify changed that quite a long time ago.
I am not sure why they didn't yet do that, but they will have to adapt their system sooner or later.
Overall, all new subscription apps in Shopify have to process prepaid orders like that, where Shopify schedules the fulfillments directly on the order itself.
If you are experiencing an issue where the fulfillments for prepaid orders aren't showing up in Shipstation, then it will be best to contact Shipstation about this, as they just have to adjust their system to recognize multiple fulfillments on orders. They should be able to get all this info directly from Shopify's API.
If they experience any problems with the Shopify API, they can also get this info from our API: https://www.sealsubscriptions.com/articles/merchant-api-documentation
We apologize that we can't provide some kind of a workaround or solution for that. But this is beyond our reach, as the scheduled fulfillments are scheduled by Shopify automatically for all prepaid orders. And we can't control Shipstation's code from our side.