Spammed By Cell C

I receive SMS messages from Cell C on a daily basis. These include specials, marketing etc. I have opted out via the website, but I am still constantly receiving these SMSes. This is for my wife as well as myself. I am no longer even a customer anymore. But I consantly get these SMSes.

I would not like to receive ANY further SMSes from Cell C. Please remove me and my wife from your list.