Did you happen to have an x-request-id from this request? Feel free to share that along with the exact request that you are making, and that will help us investigate what’s happening. Cheers!
No worries! So I’ve taken a look into things here - a custom Shipping App on this particular store automatically archives the order immediately once the fulfillment has been performed which affects the order status - order status moves to the ‘closed’ state when it is archived.
The majority of the orders on the store (bar those 7 that are still open) are all in the ‘closed’ status.
I could see your app has the read_all_orders scope (so can read past 60 days), and I’ve been testing out the GET call on the store, I would try adding orders?status=any to your call for this store.
That would pull in all orders, irrespective of the order status(docs). Let me know how that goes! Thanks.