Paginate with Descending Timestamp in Firestore

Question

Im having trouble paginating data by its descending timestamp in Firestore (fetch newest first). When I order by

Firestore.firestore().collection("items")
        .order(by: "date", descending: true)
        .limit(to: 3)

it works, but if I try to refresh it just loads the same data. To paginate I tried

Firestore.firestore().collection("items")
        .order(by: "random", descending: true)
        .start(after: [lastFetchedItem?.random ?? ""])
        .limit(to: 1)

which fetches data based on a random number generator and it paginates perfectly each time so I know its possible. Now if I try

Firestore.firestore().collection("items")
        .order(by: "date", descending: true)
        .start(after: [lastFetchedItem?.date ?? ""])
        .limit(to: 1)

I load the first item but can't paginate to the next. I record the timestamp with Timestamp(date: Date()) and in my dictionary my date is written as

var date: Date?
    
    init(dictionary: [String: Any]) {
        self.date = dictionary["date"] as? Date
    }

Answer 1

I ended up formatting the date field as a unix timestamp which gave me an Int such as I did with .random. Then I ordered by the date. Works perfectly.