Sim Swap done without my authorisation

A Sim swap was done on my number by someone whom I do not know. As a result I was de*****ed and my bank account was emptied by ********** via cell phone banking. When I went to enquire about why my number was not working, I was faced with unhelpful and extremely rude staff at vodacom. I do not understand why I was treated so poorly when none of this was my fault but the fault of the service provider who failed to protect my information. I am extremely dissatisfied with both Vodacom and Capitrc bank