Simcard not activated and not answering

Hi, I was called a week ago with an offer to upgrade my existing Telkom Mobile contract. I accepted the deal that the lady offered and was told that they would deliver in last week. I received the package in last week from a company called SellDirect, so firstly I want to know where they got my details from and why nobody answers the phone? I have spent hours of phone time trying to activate my sim card. If it is not done by the end of the day I am cancelling the deal. Telkom says they can't help me but how can they give out my personal details to a third party?