Wrongly billed for using internet data

Hi had switched from 2G plan to 3G for discount provided for two months .
Post two months when i requested to move back to original plan it was activated only for 5 days post which they randomly assigned another plan without my initiation or approval or acceptance which laid me pay rs 8500 approx instead of ideal bill not more than Rs 800.Though they have approved partial reversal of Rs 5800 i am still asked to pay Rs 2700 instead of my ideal bill expected around Rs 800 which i am ready to pay .And intention behind changing the plan was to save money but in return it asked more money if i wont have asked to move from 3G to 2G max bill would have been not more than 1000.

Complaint number raised at vodafone end which approved only 5800 instead of expected 7500 is
1706468338

Being using corporate plan i have to face this issue .I am using this number since 4-5 years