order not received but still d status is delivered

I ordered 2 books of history n geography for civil service exam. The delivery date was 27th sept 2014. On 27th i got a call to confirm d order but i didn’t receive it n i told him so. I called d customer support no n i was shocked to hear that my order has been delivered on 24th sept 2014. I already have paid for my order but i m with empty hands. I also on their e mail address but there answers r not satisfactory. Please guide what shud i do