Aircel
Cost charged for pocket internet

I have Aircel Pocket internet (Rs.98 plan). I just bought the sim card for surfing.

They say its free unlimited browsing and download (provided 10p/10kb after 30 days activation).

But surprisingly, on the first day, my account balanced was deducted by 5 rupees (and i didn't make any contacts from it).

Can anybody tell me its Reason???