Consumer Redressal

I am a Vodafone postpaid customer.I usually get my bill around 300 to 400. According to vodafone they have unbilled credit limit . They had set my credit limit to 1200 and on 26th of May they sent me a sms that my usage is around 1983 Rs[ This usage does not deduct the free services i get in plan which if deducted my usuage wud be around 400Rs ].They say now I have to pay 80% of usage i.e 1983 Rs or my outgoings and internet will be blocked which they did within few hrs of sending sms.My argument is that why should I pay more than my actual bill if they are keeping credit limit they should count credit limit after deducting the free services they offered me. When my actual bill even according to them won\'t be even 500Rs why should I pay 80% of 1983 Rs.They have blocked my outgoing calls and stopped my internet service.I have lost so many important calls and it has caused me mental pressure. I request you to help as this so unfair why should I pay more money than what the actual bill is