Cant get Invoice off my email.

I keep getting a vodacom invoice on my email. I have been at the vodacom shop in Key-west, Krugersdorp twice to stop it, and I have phoned the vodacom helpline a couple of times, each time holding on for an hour plus, to talk to someone who promises me it is fixed, and I wont receive the invoice any more. Just to receive it again next month. I am not a vodacom client!!!! I don't want the email, but it seems impossible for them to remove my address.