Revocation handling for iOS In-App-Purchase subscriptions

I've searched for a solution for hours but haven't found one yet.

I have a freemium app where you can buy 3 month plans via IOS IAP or Stripe.

When a customer purchases through the strip and their card fails or when they unsubscribe, my app receives a web check and I can flag that customer as an offense. That way I can report that the client is lost and take action to reconnect them.

However, with iOS, I don't seem to have this option. One solution to this would be to keep the marker in my database for start_date

, and renewal_date

that subscription and mark them as lost only in the event of payment failure.

This would be quite inconvenient and I was wondering if there is a better way to check with iTunes if the connection is canceled.