What could be wrong with this Realm schema?

Question

I am trying to open a new Realm db file using realm-cpp sdk with the following schema that includes nested objects

struct Card : realm::object<Card> {
    realm::persisted<realm::object_id> _id{realm::object_id::generate()};
    realm::persisted<std::string> name;
    realm::persisted<std::string> question;
    realm::persisted<std::vector<std::string>> options;

    static constexpr auto schema =
        realm::schema("Card",
                      realm::property<&Card::_id, true>("_id"),
                      realm::property<&Card::name>("name"),
                      realm::property<&Card::question>("question"),
                      realm::property<&Card::options>("options")
        );
  };

struct Deck : realm::object<Deck> {
    realm::persisted<realm::object_id> _id{realm::object_id::generate()};
    realm::persisted<std::string> name;
    realm::persisted<std::vector<Card>> cards;

    static constexpr auto schema =
        realm::schema("Deck",
                      realm::property<&Deck::_id, true>("_id"),
                      realm::property<&Deck::name>("name"),
                      realm::property<&Deck::cards>("cards")
        );

  };

auto realm = realm::open<Deck>({dbFile});

If I remove the nested property realm::persisted<std::vector<Card>> cards, everything works as expected. But when I add the nested object, it gives runtime exception:

DB: 30017 Thread 0x108a6c580: Open file: ./test.db/realm.db
libc++abi: terminating with uncaught exception of type realm::SchemaValidationException: Schema validation failed due to the following errors:
- Property 'Deck.cards' of type 'array' has unknown object type 'Card'

Process finished with exit code 134 (interrupted by signal 6: SIGABRT)

Could you suggest what could be wrong with my db schema?

Versions:

• realm-cpp sdk alpha
• cmake 3.18.1
• macOS Monterey 12.6.5
• Apple clang version 14.0.0 (clang-1400.0.29.202). Target: arm64-apple-darwin21.6.0.