Capitec bank unauthorized debit order dispute refusal

A clientele debit order if R382 was transacted from my Capitec bank account without my consent, I tried to dispute the debit order but Capitec the bank I've been using for quite some time would not allow me. I do not know nor have any knowledge signing any agreement with Clientele. Why would a bank prohibit it's customers from disputing such? It raises eyebrows to the public we're meant to get great service but we're told to dispute with the service provider (Clientele) to cancel, why? I'm not happy at all with their service that money is to feed my family not for some company to easily debit however they feel. Maybe it's high time I changed my bank because this one is so unprofessional