I'm actively working with Apple support on this same thing. Not sure if you can see this:
https://feedbackassistant.apple.com/feedback/13242068
But essentially, in production, no device gets back any of my subscriptions.
Works in dev in simulator and on-device and even for the approval process, but not at all in production.
If I get anything back that helps I'll follow up here, but my gut is now that there is a StoreKit 2 issue.