Airtel — Regarding internet Data

Internet data is not working on my mobile since 1st December and it's not happening first time, it has also happened back in the month of October. I don't know why this is happening .
I have complained many a times and after 7-10 days Airtel used to send me a message like your complaint has been resolved but nothing changed, still I'm facing the problem.
I was forced to buy new Sim card as sometimes there was problem while calling also.
My money wasted. Airtel decieved me at critical times.
Please look into this matter and refund my money also.
Tarun
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