LOTTOLAND SPAM!

Good day. Can anyone please assist me that has perhaps been through what I am about to explain. I cant even remember registering with Lottoland. I have tried to block the annoying sms's that I am receiving on a daily basis. (15 to 20) and more. But to no avail. They probably have hundred of numbers that they sms from! Please can someone assist in this regard. I have even tried online on the website but I am not even registered with them. Otherwise if someone could assist with who and where I can log a complaint. It has now gotten me into trouble at work as they are presuming that I am not working and wasting time that I am being paid for on my phone. PLEASE HELP!