View in SwiftUI does not get updated when model changes

I am inserting a new item into the modelContext (while on the single Deck) and the view is supposed to update automatically, but it does not. It refreshes only when I navigate back from a single Deck view to the list of Decks view. I am not sure what I am doing wrong here.

*It also does not work when I delete a card from the deck

It just seems like I am passing a value instead of a reference somewhere. But I cannot spot where.

My Views structure looks like this:

• Decks View (list of decks)
  • Deck View (list of cards in a deck - I am adding a new card from this view)
    • Card View (single card)

private func addCard() {
  let newCard = Card(
    front: front,
    deck: cardModel.deck!
  )
            
  withAnimation {
    modelContext.insert(newCard)
  }
}

CardModel stores the deck (I make sure the Deck is not nil before I try to insert a new Card into context):

@Observable
final class CardModel {
    var deck: Deck? = nil

    public func showAddSheet(deck: Deck) -> Void {
        self.deck = deck
    }
}

Deck model:

@Model
final class Deck {
    @Relationship(.cascade)
    var cards: [Card]? = [Card]()
    var name: String = ""
    
    init(name: String) {
        self.cards = [Card]()
        self.name = name
    }
}

Card model:

@Model
final class Card {
    @Relationship(inverse: \Deck.cards)
    var deck: Deck? = nil
    var front: String = ""
    
    init(front: String, deck: Deck) {
        self.deck = deck
        self.front = front
    }
}

Router class:

enum Path: Hashable {
    case decks
    case deck(Deck)
}

@Observable
final class RouterModel {
    var path: [Path] = [Path]()
}

Decks view:

struct DecksView: View {
    @Query() var decks: [Deck]

    var body: some View {
        List {
            NavigationStack(path: $routerModel.path) {
                ForEach(decks, id: \.self) { deck in
                    NavigationLink(value: Path.deck(deck)) {
                        Text(deck.name)
                    }
                }
            }
        }
        .navigationDestination(for: Path.self, destination: { path in
                switch path {
                    case .decks:
                        DecksView()
                    case let .deck(deck):
                        DeckView(deck: deck)
                    case let .card(card):
                        CardView(card: card)
                }
            })
    }
}

Deck view:

struct DeckView: View {
    var deck: Deck
    
    var body: some View {
        List {
            ForEach(cards) { card in
                VStack {
                    Text(card.front)
                }
            }
        }
    }
}