Customer confidential data leak/breach

There seem to be data breach or data leaks within Vodacom. I am getting random calls from people claiming to be from Vodacom. What's alarming is they know my name, the type of product/contract I have and even the device I use. They even knew exactly when the contact expires. Such information is only known by Vodacom. Us consumers we do our part to protect ourselves and I believe service providers must do their part. Someone is leaking customer information (enough to use as bait) for these ********!!!