Vodafone — Cheated by introducing new postpaid plan

Actualy iam using vodafone prepaid connection.One day i received a call from vodafone customer service, saying that they are introducing new postpaid tarrif plan i.e.monthly rent is 199Rs/-. Also they said that, i can active to any another vodafone number for free to talk for 24hr's from my mobile number which i will use frequently and 50Rs/- will get deducted from 199Rs/- for that vodafone number(which i have activated to talk freely). And also to pay 300Rs/- in advance. So i have payed 300Rs/- and i took the sim.
Now my OUTGOING call has been cancelld. I have called to customer care and asked for the detail.
Now they are asking me to pay the bill of Rs.2227. This vodafone people has cheated me by billing for the number which i have activated for free. Also they are asking me to pay credit limit amount of 1200Rs/- also. They didnot inform me about this credit limit only and now they are asking me to pay that amount also.