Unauthorized Showmax activation.

Showmax has been activated into my account without my permission. When I check the process of adding showmax to your DSTV account, it requires my ID number and an OTP number to my phone, I've never provided my ID number to Showmax and never received an OTP on my phone. How is it that it was added? how do I know that this won't happen again? Is multichoice giving 3rd party companies our details? this is *****