M-Web & Discovery ********* and immoral business practice!

How's this for a nice ****! I recently cancelled my Vitality subscription as the benefits are non-existent. Lo and behold I start getting debit orders from M-Web who I have never done business with. I instructed FNB to reverse the debit order only for it to pop up again. And once again it pops up. Phoned M-Web only to be told that Discovery had advised that I had a "free" discovery mail address and that they can bill me. Firstly I haven't used the email for months. Secondly I cancelled in December 2018. Thirdly no notification from either party. Fourthly I have no contractual relationship with M-Web. However, that doesn't seem to phase big business who just goes ahead and bills me. Immoral ********* and I don't know the law very well but I consider this to be *******. The cherry on the top is that I have just received an no-reply email to say they are sorry I am cancelling my account (?) and they have the audacity to charge me one month cancellation.