Rude contact centre people and spam calls.

I have been constantly harassed by the rudest people. Calling from the following numbers: +***, +***, +***. They say they are calling on behalf of cartrack. I keep blocking these numbers and they continue to call me. I asked where they got my contact details from they said the Direct Marketing Association which is a lie as I am marked on the Do Not Contact list for everything. When I request they must not phone me they continue to do so and they are rude, swear at me and tell me they dont care, they have targets to reach. So I demand the head of your call centre division contacts me to tell me why they do no respect my DNC mandate, why they allow people to talk to anyone like that while representing their company. I will never ever use car track in my life because of this. I hope no one else does either. Also I will be reporting this to the POPIA watchdog as a gross violation of the law.