POPIA infringement

I'm a client of FFW and they are spamming me with up to 6 calls a day trying to upsell me. I've asked to be removed from their contact list and they just carry on with the calls. It seems as though they need to be reported for POPIA infringement before they'll stop. I've tried emailing them (2 days ago) and have been called 8 times since to upsell me - not to resolve the issue, mind.