Someone did a sim swop on my mom's mobile number without her approval, meaning the hijacked her number and WhatsApp

Someone did a sim swop on my mom's mobile number without her approval, meaning the hijacked her number and WhatsApp. They have once attempted to **** her contacts. My mom has gone to Vodacom for assistance and they did not attempt to help her at all - they simply told her there's nothing they can do. They didn't bother to explain why or how her number was swopped without her knowledge, nor attempt to reclaim her WhatsApp. They just sent her packing. If you are on a Pre paid number you will be susceptible to this type of **** and Vodacom will do absolutely nothing to help. This is appalling because how do they just allow for sim swops without authorisation? Surely there's POPI acts and consumer rights being infringed.