I DO NOT OWN A TV Licence

About 2 years ago I enquired about a tv that was on special at Makro in Alberton , I really loved the tv & the price was great so I said to the sales person I will come back the following day but then he asked for my details & said I should ask for him when I come back , I ended up not buying that tv ...then out of the blue I started to receive smses saying I should pay for my tv licence , I have sent a number of of responses explaining that I dont even know what a tv licence looks like & I do not own any tv and yet I keep on getting their smses . What must I do for them to leave me alone