Vodacom Data Contract *******

I see that there many complaints about data being used by Media Streaming or VOIP and I am a victim of this. I do not have any live stream games but my 50G data bundle is finished by mid month. When I check the daily usage, the Media Streaming or VOIP is using almost 1.5G a day. I called Vodacom to complain about this and was told that it will be checked and they will get back to me. This was in mid January and I have not received any feedback. When I requested for the contract to be canceled they informed me that I cannot cancel the contract. I just want this rectified or the contract canceled as I am paying for a service that I do not benefit from. This was the biggest mistake I made and the media should know about it.