Nedbank Worst Customer service

what a frustrating time with Nedbank,, they offer me exorbitant buildings insurance which I then cancel with them after their requirements sent to me, they confirm via text that their insurance is canceled but still their charge goes off my account going against they communication and promise of not charging the insurance, after numerous calls and transfers via their call center stiil no luck, I proceeded to fourways branch they still connect me to an agent that advised me that his manager or will call me back it's been 48hrs and no email no call, I should just accept their non customer centric behavior, they took money from my account now they won't refund me, so I paid double insurance fees, and I will now seek help from the banking Ombudsman