Themobilestore — replacement of the handset

My order id is 9004359.I had recieved tampered sealed handset about which I had mailed to themobilestore. So they collected the handset on 25 / 07 / 2014. They sent sales person from maxsus mall bhayandar west and said they would be replacing it by Monday (28/07/2014). Their senior named sachin who assured me about the replacement after reminding him twice on monday is not taking my calls.I am attaching the snap - shot of the acknowledgement given in writing to me by their representative and his seniors number. I had placed prepaid order on the 14 / 07 / 2014. Its bee s night mare purchasing from them.