MTN **** and poor customer service

I'm very disappointed in MTN and their poor customer service with regards to my stepfather who had been a loyal client for all these years. My stepfather had been the target of a ***** **** in which he had to pay R15 000 for sms bundles. He contacted MTN and they informed him that they have been aware of these ****s and that my stepfather had to file a case at the police department which he did and submitted the affidavit and police report to MTN. Even after submitting the documents my stepfather received numerous messages and calls from MTN collections department threatening to hand him over. And even after explaining his situation over and over again they kept calling. This really had an impact on his health as he was constantly worried. My stepfather has since passed on. I've contacted the customer service department and was told to send the death certificate and that the case was going to be closed. Still we receive calls and messages. I've also asked the lady at customer service to change his number to prepaid as we still get calls from people and companies who has not been informed of his passing. Only to learn that the service on his phone has been suspended.