Ajax not working with Node js - Express js

Im trying to send data from my server side to my client side with ajax but when i use res.send(data) in node, it show me a empty html with the data and i want to get data from my client side without reloading the page and edit something in my actual html

Here's my server-side code

    app.post('/',(req,res)=>{
    var userName = req.body.username;
    var password = req.body.password;

    connection.query('SELECT * from admin',(err, rows, fields)=> {
      if (!err){
        if((userName == rows[0].usuario) && (password == rows[0].contraseña)){
            res.sendStatus(200);    

        }else{
            res.send('Incorrect username or password')
        }
      }else{
        res.send('Error while performing Query.');
      }

    });

});

Here's my client-side code

$(document).ready(function(){
$('#login-form').submit(function (e) {
        setTimeout(function () {
        e.preventDefault();
        $.ajax({
            type: 'POST',
            url: '/',
            dataType: 'jsonp',
            data: ({username: $('input[name=username]'),password: $('input[name=password]')}),
            success: function(data,textStatus){
                if(textStatus.statusCode == 200) {
                    $('.error-user').html('Succes');    
                }else{
                    $('.error-user').html('Not Success');
                }


            },
        });
        }, 1000);

});       
});

UPDATE: I removed the setTimeOut() but when I submit the form the page freeze like two seconds and then nothing happen, I get this 'error Maximum call stack size exceeded', dont get me data just stay in the same view if like post method was never called

UPDATE-FINAL: I got values from input outside of the ajax and it works nice,thanks :#