Cheated on tata photon + connection

I took tata photon+ in infosys limited bangalore.The seller told me that the connection cost 1200rs.He will be giving 2 months free usage.The bill will be generated from 3rd month.But the bill got generated every month.They DID not pay heed 2 my call also. I purchased the connection on 30th april 2012.And they disconnected it on may 24.I DID not even use it for 2 complete months.Now after disconnection also I am getting the bill.The bill amount is now raised to 1900 rs.I am completely cheated on this.