Showmax free 14-day trial is a **** and Showmax continues to deduct money in my bank account

I tried the free 14-day trial from Showmax but before I could start the free 14-day trial Showmax required my Banking details and said they will not take any money from my bank account and it was just for security measures. Then I put in my Banking details and started watching. But I did not like the shows on Showmax and I went back to the Showmax website to cancel the trial before the 14 days. But then Showmax has been deducting money in my bank account. I tried everything to make them stop, but they continue. This is evil and pure **** because I have unsubscribed to their trial they claim to be free and if they do not stop now I have to cancel my bank card which I use for other important things.