Taking money without my concent unfairly

I am very unhappy that Discovery keep on charging me and taking money from my bank account, without my approval. Every time they deduct there is a bank charge of R70 involve. Every time I need to reverse it. This is happening now every month. I am sick and tired of this. I paid this already in 2016. I also complained on hello peter about this. They kept on doing it, since 2017 started again. I have the proof of payment with me. I demand this to stop and refund the bank charges