Constant cold calling by Elite Mobile

My wife and I keep on getting cold called about the offers from Elite mobile which they say are on behalf of Vodacom. I did NOT request to be called and do NOT want to be marketed to.<br> <br> They refuse to take NO for an answer and keep telling me they will add me to the do not call list however we still keep getting phoned.<br> <br> Please take this up immediately as I do not want to be constantly bothered with these calls!