ios – Why does my TableViewCell does not present different knowledge

I meant to show knowledge from my Firestore Database into my app utilizing the TableViewCell. It supposed to point out the bookTitle, bookAuthor and bookSummary however the bookAuthor doesn’t present up. Beneath is my code.

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = UITableViewCell(fashion: .subtitle, reuseIdentifier: "cell")
        cell.accessoryType = .disclosureIndicator
        cell.textLabel?.textual content = books[indexPath.row].bookTitle
        cell.textLabel?.font = .systemFont(ofSize: 20, weight: .medium)
        cell.detailTextLabel?.textual content = books[indexPath.row].bookAuthor
        cell.detailTextLabel?.textual content = books[indexPath.row].bookSummary
        return cell
    }
    
    
    func setupTableView() {
        view.addSubview(tableView)
        tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
        tableView.allowsSelection = true
        tableView.isUserInteractionEnabled = true
        tableView.translatesAutoresizingMaskIntoConstraints = false
        tableView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
        tableView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
        tableView.rightAnchor.constraint(equalTo: view.safeAreaLayoutGuide.rightAnchor).isActive = true
        tableView.leftAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leftAnchor).isActive = true
    }
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection part: Int) -> Int {
        return books.depend
    }

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