Ajax redirects to url

Good morning guys,

I'm having a little problem, I guess it's simple, but I can not solve it.

Next, I have to upload a user profile photo, the code is working beauty:

  

JAVASCRIPT

$(".change-photograph").change(function (event) {
        var fileName = $(this).val();
        var ext = fileName.substring(fileName.lastIndexOf(".") + 1);
        if (ext == "gif" || ext == "jpg" || ext == "jpeg" || ext == "png") {
            var reader = new FileReader();
            $(reader).load(function (event) {
                $(".img-photograph").attr("src", event.target.result);
            });
            reader.readAsDataURL(event.target.files[0]);

            $("#save-photograph").click();
        } else {
            dialog("Alerta", "O arquivo selecionado é inválido.")
        }
    });
$("#uploadPhotograph").submit(function () {
        var formData = new FormData($("#uploadPhotograph")[0]);

        $.ajax({
            type: "post",
            url: "/User/UploadPhotograph",
            ajaxasync: true,
            data: formData,
            success: function () {
                addMensagem("Foto alterada com sucesso.");
            },
            error: function (data) {
                alert(data.x);
            }
        });
        return false;
    });
function addMensagem(mensage) {
$("#mensagens").append("<li style='overflow: hidden; margin: 4px 0px; border-radius: 2px; border: 1px solid rgb(124, 221, 119); box-shadow: rgba(0, 0, 0, 0.0980392) 0px 2px 4px; color: darkgreen; width: 310px; cursor: pointer; height: 52px; background-color: rgb(188, 245, 188);' class='close-mensagem animated flipInX'><div class='noty_bar noty_type_success'><div class='noty_message' style='font-size: 13px; line-height: 16px; text-align: center; padding: 10px; width: auto; position: relative;'><span class='noty_text'>" + mensage + "</span></div></div></li>");

}

  

C #

[HttpPost]
    public ActionResult UploadPhotograph(UserViewModel user, HttpPostedFileBase file)
    {
        if (file != null)
        {
            var edit = false;
            if (user.user_photograph != null)
            {
                if (System.IO.File.Exists(Server.MapPath("~/" + user.user_photograph)))
                {
                    System.IO.File.Delete(Server.MapPath("~/" + user.user_photograph));
                }
            }
            else
            {
                edit = true;
            }

            String[] strName = file.FileName.Split('.');
            String strExt = strName[strName.Count() - 1];
            string pathSave = String.Format("{0}{1}.{2}", Server.MapPath("~/assets/usersPhoto/"), user.Id, strExt);
            String pathBase = String.Format("/assets/usersPhoto/{0}.{1}", user.Id, strExt);
            file.SaveAs(pathSave);

            if (edit)
                _userAppService.EditPhotograph(user.Id, pathBase);
        }

        return new HttpStatusCodeResult(System.Net.HttpStatusCode.OK);
    }

My problem is that after he realizes that everything cute he redirects to this view, he had to continue in the user profile, not redirect to any place. Someone knows what's going on, I have no idea what it might be.

Thanks in advance!