В чем заключается ошибка, которую я делаю при попытке получить данные в UITableView из этого ответа API?

Question

Я получаю ответ API, который мне нужно загрузить в UITableView:

{"count":2,"next":null,"previous":null,"results":[{"id":168,"contact":{"id":303,"avatar":null,"userId":249,"phone":"46528","rate":0.0,"firstName":"Jack","middleName":null,"lastName":null,"categories":[],"isContractor":false,"isIndividual":false,"isActive":true,"workspaceId":298,"workspaceTitle":"SomeAnotherCompany","workspaceLogo":null,"vatNumber":691102002},"contactId":303,"workspaceId":302,"isCustomer":false},{"id":169,"contact":{"id":348,"avatar":null,"userId":280,"phone":"+123123123","rate":0.0,"firstName":"Doe","middleName":null,"lastName":"John","categories":[{"id":221,"title":"IT Consulting","category":145,"workspaceCategory":434,"workspaceUser":348}],"isContractor":true,"isIndividual":false,"isActive":true,"workspaceId":342,"workspaceTitle":"ООО \"SomeCompany\"","workspaceLogo":null,"vatNumber":192532321},"contactId":348,"workspaceId":302,"isCustomer":false}]}

Я пытаюсь загрузить следующие значения в ячейку: - firstName - скорость - аватар - телефон - WorkspaceTitle

, но метки отображаются пустыми, или мое приложение вылетает.Вот мой код:

    func getData() {
            DispatchQueue.main.async {

                let headers = [
                    "content-type" : "application/x-www-form-urlencoded",
                    "cache-control": "no-cache",
                    "Authorization": "JWT \(access)"
                ]

                let request = NSMutableURLRequest(url: NSURL(string: "https://SomeApi.com")! as URL,
                                                  cachePolicy: .useProtocolCachePolicy,
                                                  timeoutInterval: 10.0)
                request.httpMethod          = "GET"
                request.allHTTPHeaderFields = headers
             //   request.httpBody            = postData as Data

                let session  = URLSession.shared
                let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
                    if (error != nil) {
                        print(error!)
                    } else {
                        if let dataNew = data, let responseString = String(data: dataNew, encoding: .utf8) {
                            print(responseString)

                            let dict = self.convertToDictionary(text: responseString)
                            print(dict?["results"] as Any)
                            self.responseArray = (dict?["results"] as! NSArray) as! [PerformersViewController.JSONDictionary]
                            DispatchQueue.main.async {
                                self.tableView.reloadData()
                            }

                        }

                    }

                })

                dataTask.resume()
            }
        }

        func convertToDictionary(text: String) -> [String: Any]? {
            if let data = text.data(using: .utf8) {
                do {
                    return try JSONSerialization.jsonObject(with: data, options: []) as? [String: Any]

                } catch {
                    print(error.localizedDescription)
                }
            }
            return nil
        }

Пожалуйста, кто-нибудь укажет мою ошибку.Вот как я пытаюсь загрузить данные в свою ячейку:

let getPeopleData = responseArray[indexPath.row]
    cell.performerImage.image = getPeopleData["avatar"] as? UIImage
    cell.performerNameLabel.text = getPeopleData["firstName"] as? String
    cell.ratingLabel.text = String(getPeopleData["rate"] as? Int ?? 0)
    cell.phoneNumberLabel.text = getPeopleData["phone"] as? String
    cell.companyTitleLabel.text = getPeopleData["workspaceTitle"] as? String
    return cell