Incorrect person information captured

They have been sending me massages that I have an account in arrears with Netstar and I should pay using an FNB account which they keep sending to me as well. I called several times for them to fix or remove my cellphone number from their system because they are sending/ directing the messages to the wrong person. The last call I had chat with them they promised to update or remove my number but I still receive the arrears massages. My problem with them is that I am covered with Netstar as well and I don’t have any arrears or problems with Netstar and now this attorney company have my cellphone number linked to someone in arrears I guess.