********** charge to bank account

I cancelled my DSTV in 2018 due to poor service and poor value for money. In March 2021 I noted a R900 charge from them on bankaccount. After spending 4 hours jumping from one to other person and being on hold for hours they told me the "computor" auto activated my account. They refuse to delete my account from their system even though I am not a customer.....are they artificially increasing their revenue by billing ex customers from their data base....? Watch out, they ******....and very evading...