How to fix the redirect?

Question

htaccess

Good day and because of what the redirect may not work.
Already reviewed any cases. Even used Meta Refresh with no result. I use OpenServer, the latest version. PHP7
.htaccess

RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-l
RewriteRule ^(.*)$ index.php [QSA,L]

I use Ajax request

function send_post(url, name, data = '') {
    var form = '';
    if (data) {
        $.each(data.split('.'), function(k, v) {
            form += '&' + v + '=' + $('#' + v).val();
        });
    }
    $.ajax({
        type: 'POST',
        url: '/' + url,
        data: name + '_f=1' + form,
        cache: false,
        success: function(result) {

            var obj = jQuery.parseJSON(result);
            if (obj.go)
                go(obj.go);
            else
                $('.loaderAjax').html(obj.message);
        }
    });
}

Checking the same

if ($find_users->pass === $_POST['pass']) {
            header('location: /');
            exit;
        }