Cold Calling | SPAM Calls

I keep on getting calls from Cartrack on my company phone and I have requested them for the second time now to remove my number, the agent said she cannot do that. She then went on to say, according to the POPIA Act 69.11 they can phone unless I complain, or go to the consumer council. Aking to be removed is not a request it is an instruction. How did you get this number legally?