DSTV WONT AUTOMATICALLY 'UNSUBSCRIBE' YOU FROM THEIR NEWSLETTER EMAILS

I cancelled my DSTV subscription about 5 years ago. I recently started getting 'newsletter' emails from DSTV which I don't want. When I try to 'unsubscribe' from their mailing list, it takes you too their website and asks you to log into your account. I don't want to log into my account. I just want DSTV to automatically remove me from their mailing list. I don't want to receive any 'newsletter/promotions/info/etc' emails from them.