Xcode have two buttons open two different view controllers : I am having trouble with this code:

    import UIKit

    class ViewController: UIViewController {

    @IBOutlet weak var team1Field: UITextField!
    @IBAction func rules(_ sender: Any)
    {
        performSegue(withIdentifier: "rulesegue", sender: self)
    }
    
    @IBAction func start(_ sender: Any)
    {
        if team1Field.text != ""
        {
            performSegue(withIdentifier: "segue", sender: self)
        }
    }
    
    override func prepare(for segue: UIStoryboardSegue, sender: Any?)
    {
        let secondController = segue.destination as! SecondViewController
        secondController.team1String = team1Field.text!
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
  
    }
    }

please keep in mind I am a beginner so you might need to dumb it down for me.

I have a "home screen" and on that screen I have a text input for the user to enter their team name. then two buttons "start" and "rules"

Start goes to SecondViewController and I am trying to get "rules" to open rulesViewController by executing "rulesegue"

on this line of code I am getting the following error: "Thread 1: signal SIGABRT"

     let secondController = segue.destination as! SecondViewController

not sure why :/