Swift CRUD ios app

I received an error when I clicked to the button delete in my app . Iwant to delete data from database MySql + PHP :
Error Domain=NSCocoaErrorDomain Code=3840 “JSON text did not start with array or object and option to allow fragments not set.” UserInfo={NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set.}
ViewController–>my code

import UIKit

class ViewController: UIViewController {

@IBOutlet weak var id: UITextField!

//Send user data to server side
@IBAction func deleteData(_ sender: AnyObject) {
    //Send user data to server side
    let myUrl = NSURL(string: "");
    let request = NSMutableURLRequest(URL:myUrl!);
    request.HTTPMethod = "POST";
    let postString = "id=\(id)";
    request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding);
    let task = NSURLSession.sharedSession().dataTaskWithRequest(request)
        data, response, error in
        if error != nil {
            let json = try NSJSONSerialization.JSONObjectWithData(data!, options: .MutableContainers) as? NSDictionary
            if let parseJSON=json{
                var resultValue = parseJSON["status"] as! String
                print("result: \(resultValue)")
                var isUserRegistered:Bool = false;
                if(resultValue=="Success") {isUserRegistered = true;  }
                var messageToDisplay:String = parseJSON["status"] as! String
                    messageToDisplay = parseJSON["message"] as! String;
                //self.store.storeName = self.lblName.text!
                //store?.sName = txtName.text!
                self.store.storeName = self.lblName.text!
                dispatch_async(dispatch_get_main_queue(), {
                    // Display alert message with confirmation.
                    var myAlert = UIAlertController(title:"Alert", message:messageToDisplay, preferredStyle: UIAlertControllerStyle.Alert);
                    let okAction = UIAlertAction(title: "Ok", style: UIAlertActionStyle.Default) {action in
                        self.dismissViewControllerAnimated(true, completion:nil);
                    self.presentViewController(myAlert, animated: true, completion:nil);

override func viewDidLoad() {
    // Do any additional setup after loading the view, typically from a nib.

override func didReceiveMemoryWarning() {
    // Dispose of any resources that can be recreated.