Mr Price money call center agents, unprofessional attitude

I love shopping at mr price, enjoy the quality of their clothes and other but lately. The issue i have is with the Mr Price money department, their call center agents have no sense of customer service on a daily occasions I receive calls from them requesting I confirm my personal details, the attitude changes immediately I explain I don't share my personal details over the phone, they become short tempered, raise their voice at me and get really emotional. When I further say i have no way of knowing they are whom they say they are, there's aggression and eventually drop the phone in my ear, only to call again later in the day and the following day. I view this as harassment and I believe their system is flawed, because the security of their call works only one way, which their way.