Uncaught SyntaxError: Unexpected token N in JSON at position 1

Прошу помочь с ошибкой ...

Ошибка:

   at Function.parse [as parseJSON] (<anonymous>)
   at Object.success (form.js:13:19)
   at i (jquery.js:2:28017)
   at Object.fireWith [as resolveWith] (jquery.js:2:28783)
   at A (jquery.js:4:14035)
   at XMLHttpRequest.<anonymous> (jquery.js:4:16323)

Файл form.js

    $('form').submit(function(event) {
        var json;
        event.preventDefault();
        $.ajax({
            type: $(this).attr('method'),
            url: $(this).attr('action'),
            data: new FormData(this),
            contentType: false,
            cache: false,
            processData: false,
            success: function(result) {
                json = jQuery.parseJSON(result);
                if (json.url) {
                    window.location.href = '/' + json.url;
                } else {
                    alert(json.status + ' - ' + json.message);
                }
            },
        });
    });
});```