Vodafone’s cheating

Hi, Am tarak from kolkata, I am a userd of vodafone postpaid. I have a 2g data plan active. In regular interval vodafone charges me some time Rs 99, some time rs 149, some time rs 49 in the name of internet download. I simply dont understand who are you to charge me for what am doing at internet. Few years back this cheater service providers robed us in the name of VAS pack. now they are steeling money in the name of internet.