[AcceptVerbs(HttpVerbs.Post)]
    public ActionResult Numbers(int id, int val, int name)
    {
        int temp = val % 2;

        brojevi br = new brojevi();

        if (temp == 1 && name == 1) {

            var nmb = (from n in numbers.brojevi
                      where n.prvi_br == id
                      select n).First();

                br.prvi_br = nmb.prvi_br - 1;
            numbers.SaveChanges();
        }

        var nm = from n in numbers.brojevi
                  select n;
        return View(nm);
    }

Data table brojevi have 3 fields but I have to change(update) only one of them (prvi_br). Why my solutions doesn't save changes to database