Mweb part of cohoots with Discovery - keeps charging me for an email address after I cancel years ago.

I had an email account with Discovery Vitality. I stopped the medical aid so I went over to Mweb so I could have an email with my ADSL product. All dealings with discovery were cancelled. This is back in 2010 to 2016. Now I am told that Discovery sold that email address to Mweb and so I have been paying for the old email address which I haven't used in years and the new email address with mweb. How can Discovery sell a cancelled email address to Mweb and why would I take an email address with Mweb if I was continuing my old one? I did not agree to any of this and I only found this out when I finally cancelled my Mweb email account a few months ago. If you can produce a document showing my signature agreeing to continue the vitalitybroadband email address via Mweb then you have a leg to stand on, otherwise please stop trying to make a quick buck!