Hathway Cable & Datacom — stop sending promotional messages

I have several times requested the hathway professionals to stop sending me these msgs and to put me on dnd. On the other side, i activated dnd and still i see the msgs in my inbox every day. Can no one help me? How rude is this hathway company? Sick policies and culture!! Hathway doesn't even respond to email or my complaints for 2 years now. I don't know how this sick company would create a good image in people's minds. This is a big disgrace to all of its staff. I think hathway should quit its business in india.