Wrong postpaid bill generated by Aircel ( cell no -8898037475)

Location/place: Mumbai

Name of company/service: Aircel

My aircel postpaid plan (Cell no 8898037475)is for maharashtra /goa region with unlimited gprs plan ,but aircel added a roaming charges of data usage used in maharashtra circle(The amount is around 13000 rs).Roaming charges should not be applicable in our specified region.
Also,every postpaid card has specific limit of usage in my case it is 700 rs,exceeding the limit will cause immediate disconnect but the generated bill is 20 times more than max limit.
I have been following the case from last 1.5 month wit aircel attendants,registered complaint in andheri east aircel office and appelate, but got a very unsatisfactory response.Please do the needful.