I have scenario same as this sample project of StoreKit 2 in SwiftUI.

I am facing issue while transaction will be interrupted (like change payment method, incoming call, app close, battery died, anything...)

While buying fuel, it will available for all cars. I want to track fuel for particular car. How can I track transaction(interrupted)?

func purchase(_ product: Product) async throws -> Transaction? {
    // Begin purchasing the `Product` the user selects.
    let result = try await product.purchase()

    switch result {
    case .success(let verification):
        // Check whether the transaction is verified. If it isn't,
        // this function rethrows the verification error.
        let transaction = try checkVerified(verification)

        // The transaction is verified. Deliver content to the user.
        await updateCustomerProductStatus()

        // Always finish a transaction.
        await transaction.finish()

        return transaction
    case .userCancelled, .pending:
        return nil
    default:
        return nil
    }
}

Steps to understand the issue:

1. Go to "Shop"
2. Buy "Race Car" & "Off-road vehicle"
3. Click on "Race Car" to go in the detail page
4. Try to buying "fuel87" for "Race Car" (this scenario might be not reproducible in sandbox account)

Now, I can see "fuel87" for both car. (I know, fuel is fuel for all the car. BUT in my case I have to track "fuel" for selected car)

How can I achieve that?