Hi Naveen Kumar,
We would like to inform you that the Magzter Gold Free Trial is available only once per iTunes account.
We checked our records and see that you have activated the free trial previously using another email address. So, our system instantly charged your account for a Magzter Gold one month subscription.
We would like to inform you that our help desk has offered you store credit as a token of gesture.
If you have any queries related to this, please contact us and we will assist you with your queries.