Vodafone India — wrong inputs given by customer care and unusual charges in my postpaid bill

I have been chasing vodafone customer care from last 15 days for the chnage of plan as i am out of country and not using the plan which is on higher side.

They have added unusual amount as well in my postpaid bill. That also they are not able to explain.

I have tried multiple calls to the customer care and they always say system is down, call back in few minutes.