Transaction.latest(for:) returns nil in StoreKit 2

Using the Implementing a Store In Your App Using the StoreKit API sample code, I've successfully integrated my new APP with StoreKit 2. There is one problem though: when I call the method Transaction.latest(for:) to get the user’s latest transaction, it always returns nil.

Here's the code snippet:

guard let result = await Transaction.latest(for: myProductId) else {
    return false
}

Is this a bug with StoreKit 2, or am I doing something wrong? This happens on a physical device, running from Xcode. Thanks in advance.