Discovery refusing to give me back my money after they deducted my account without my permission

Discovery refusing to give me back money they took from me without my permission. I have a life policy with discovery and they put me into their vitality program without my consent. In September 2019 I cancelled my medical aid and Vitality with Discovery and was only left with Life cover. Only to find out that they had been *******ly added vitality into my life cover without my consent. They did not tell me that they had in fact moved the vitality into my life cover. When I asked then they agreed that they did not inform me however I should have known since they had sent a statement in December that year. This is while they had been charging me since September. They say that they sent me a statement which I never received and would have thought that it was spam if I had received it as I knew for certain that I had cancelled my vitality.

They point is that they should have informed me before they deducted my account. And now I would like to get my vitality premiums back as I only wanted a life cover from October 2017 to July 2019. I have rejoined discovery medical aid and vitality however for the periods that I did not give permission I would like to get my money back .