Why do Rain employees refuse to give their full name?

Do employees of Rain give their customers false names? Recently I spoke to a Rain employee on the phone about my account. When I asked for her name she said it is "Mbali" I then asked for her surname which she refused to give saying "I can't give you my surname".

Obviously, this is not acceptable and questionable business practice. Why would this Rain employee refuse to give her name if she does her work properly?Maybe rain needs to look into their employees.