Blu Label Telecoms Constant SMS' and Dont even have an Account

Blu Label Telecoms have got my cellphone number and keep sending me messages of transactions on an account that I don't even have with them. Sometimes I get 5-10 messages a day. I don't know where they got my cellphone number from and I don't have any business with them. I have tried to get them to remove my number and stop sending messages but their call centre centre tells me it has been done or they will log a ticket to have it done but it is still not resolved. I give up!!!!