AJAX double call on submit

AJAX double call on submit

I'm using bootstrap 3.0 form and want to do ajax submit instead of regular one.
I like bootstrap's form validation and I use preventDefault() to stop original form from firing.

but form still keeps firing on submit so I get 2 submits instead of one.
I now removed "action" url from the HTML form so it now fires on .html?parms
how do I prevent original form from firing?
I tried on "click" but bootstrap's validation stops working if I do that.


 $('#investorsSubmit').on('submit', function (e) {
        e.preventDefault();
       
       
        $('#investorsSubmit').ajaxSubmit({
            type: 'post',
            url: 'http://www.ccccc.com/php/inv.php',
            //data: $("#send-form").serialize(),
            success: function (responseText, statusText, xhr, $form) {
                $('#thanks-modal').modal('show');
                $(this).closest('form').find("input[type=text], textarea, url").val("");


            }, error: function (responce, error) {
                //alert('error');

            }
        });

        return false;


    });