表格视图单元格显示两次，不显示字幕

Question

我正在尝试创建一个提醒应用程序，但是当我添加一个类别时，该类别的名称会显示在单元格中，但描述不会显示，并且该单元格会显示两次

//this is in the view controller that has the table view
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return allCategories[section].activities.count
}
//sets the title of the cell to the name of the activity and the subtitle to the description of the activity
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "theCell", for: indexPath)
    cell.textLabel?.text = allCategories[indexPath.section].activities[indexPath.row].name
    cell.detailTextLabel?.text = allCategories[indexPath.section].activities[indexPath.row].description
    return cell
}
//this is in the view controller that creates an activity which populates activities
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "createSegue" {
    if activityName.text?.isEmpty == false {
        if let activityReminder = activityName.text {
            allCategories[addButton.tag].activities.append(Activity(name: activityReminder, description: activityDesc.text!, date: datePicker.date))
        }
    }
    }
}
 @IBAction func createP(_ sender: Any) {
    performSegue(withIdentifier: "createSegue", sender: self)
} 
//this populates allCategories
@IBAction func createPressed(_ sender: Any) {
    guard categoryNameTF.text == "" else {
    allCategories.append(Categories(name: categoryNameTF.text!, description: categoryDescription.text!, activities: []))
        dismiss(animated: true, completion: nil)
        icon = currentIcon

        return
}
}