Reliance Netconnect High Speed 1x — selling o[censored]sed modem

Address:

North 24 Parganas, West Bengal

I have bought a high-speed 1x usb modem of reliance netconnect from MAA TARA STORES near Agarpara railway station on 11/5/2012. Its price is 799 rupees. Number of the modem is [protected]. I gave the shop keeper named Nitai Mitra the documents{ xerox copy of votar id and a photo to activate the modem. Nitai told me that I will get 1 month free unlimited broadband service for 1 month. I connected net the next day. i could not acess net. i called the reliance customar care.
they told me the modem is pre activated. i can't get the free usage. Nitai sold me an used modem.
I went to MAA TARA STORES. The shop keeper Nitai didn't return me the cash and didn't took the modem back.