API通信で内容がTableViewCellに表示されない

QiitaAPIを取得して、TabeleViewCellに表示するサンプルを作成中です。
レスポンスは返ってくるのですが、Cellに表示されてスクロールすると落ちてしまいます。
（エラー内容；Thread 5: EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)）

ViewController
1import UIKit
2
3class ViewController: UIViewController {
4    
5    private var qiitaModel:[QiitaModel] = []
6    private let api = QiitaAPI()
7
8  private  let cellClassName = "TableViewCell"
9  private  let reuseId = "TableViewCell"
10    
11    @IBOutlet weak var tableView: UITableView!{
12        didSet{
13            let nibName = UINib(nibName: cellClassName, bundle: nil)
14            tableView.register(nibName, forCellReuseIdentifier: reuseId)
15            tableView.delegate = self
16            tableView.dataSource = self
17        }
18    }
19    
20    override func viewDidLoad() {
21        super.viewDidLoad()
22    //API通信する
23        api.getQiitaAPI { [self](users,error) in
24            if let _error = error {
25                    //api通信エラーが起きた時の処理
26                    debugPrint(_error)
27                    return
28        }
29    guard let _users = users else {
30                    //apiは成功してるのにレスポンスが空の時
31                    return
32                  }
33            
34            self.qiitaModel = _users
35            self.tableView.isHidden = false
36           tableView.reloadData()
37}
38}
39}
40
41extension ViewController:UITableViewDelegate,UITableViewDataSource{
42    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
43        qiitaModel.count
44    }
45    
46    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
47        guard let cell = tableView.dequeueReusableCell(withIdentifier: reuseId, for: indexPath) as? TableViewCell
48        else {
49            return UITableViewCell()
50        }
51        let user = qiitaModel[indexPath.row]
52        cell.configure(user: user)
53        return cell
54}
55    
56    func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
57        return 300
58    }
59    
60}
61

QiitaModel
1import Foundation
2
3struct QiitaModel:Codable{
4    let title:String
5    let createdat:String
6    var user: User
7    
8    enum CodingKeys: String, CodingKey {
9        case title = "title"
10        case createdat = "created_at"
11        case user = "user"
12    }
13 
14}
15
16struct User:Codable {
17    let name:String
18    let profile_image_url:String?
19    
20    
21    enum CodingKeys:String,CodingKey {
22        case name = "name"
23        case profile_image_url = "profile_image_url"
24    }
25}
26

TableViewCell
1import UIKit
2
3class TableViewCell: UITableViewCell {
4
5
6    @IBOutlet weak var iconImage: UIImageView!
7    @IBOutlet weak var nameLabel: UILabel!
8    @IBOutlet weak var titleLabel: UILabel!
9    @IBOutlet weak var createdLabel: UILabel!
10    
11    
12    
13    override func prepareForReuse() {
14        super.prepareForReuse()
15        
16        iconImage.image = nil
17        nameLabel.text = nil
18        titleLabel.text = nil
19        createdLabel.text = nil
20    }
21    
22    func configure(user:QiitaModel){
23       
24        if let iconImageUrlStr = user.user.profile_image_url {
25            iconImage.image = UIImage()
26        }
27    
28        nameLabel.text = user.user.name
29        titleLabel.text = user.title
30        createdLabel.text = user.createdat
31}
32
33
34
35}
36

QiitaAPI
1import Foundation
2
3final class QiitaAPI {
4    
5     func getQiitaAPI(completion: (([QiitaModel]?, Error?) -> Void)?){
6        guard let url = URL(string: "https://qiita.com/api/v2/items?page=1&per_page=20" ) else {return}
7        
8        var request = URLRequest(url: url)
9        request.httpMethod = "GET"
10        
11        let task = URLSession.shared.dataTask(with: url){(data,response,err) in
12            
13            if let err = err{
14                print("両方の取得に失敗しました",err)
15                return
16            }
17            if let data = data {
18                do {
19//                let json = try JSONSerialization.jsonObject(with: data, options: .fragmentsAllowed)
20                    let qiita = try JSONDecoder().decode([QiitaModel].self, from: data)
21                   completion?(qiita,nil)
22                    print("json",qiita)
23                }catch(let err){
24                    print("両方の取得に失敗しました",err)
25                }
26    
27            }
28            
29        }
30        task.resume()
31    }
32}
33