wrong commitment

Dear Sir,

With reference to above given no, I am the part of Tata DoCoMo family from
long time, but this time I am really not satisfied with the kind of service/
reply received from TATA. Around six month back one of your executive
offered one scheme of 325 Rs in that he offered 1500 local + std minutes + 3
GB monthly net on 2G for 6 month and he promised that after 6 month he will
extend net package for further. I told him very clearly that he has to inform me in advance if the same is not possible. But not received any information from TATA docomo on expiry of my pack. Now when I received my bill last month, I
shocked as I received a huge bill for DATA service. When I called call
center on 121 they replied go and talk to that executive we cant do any
think and you have to pay this amount. Even I asked to check the record of
our conversation which I had 6 month back he refused . How can I remember
the name after 6 month?. I was in impression that TATA never ever do falls
promise to their customer. i sent a mail to customer service but they refused to lodge the complain. Finally i wrote to President desk and one Miss Geeta Srivastava called and she registered the complain vide docket no 487334679. But after few days got the same reply sorry we can not reverse the charges. My simple question on what basis you have refused ? have you checked audio recording? I SINGLE WORD FOR TATA DOCOMO : HOPELESS CUSTOMER SERVICE