Constant Harassment!!

I am constantly being harassed by MBD on a daily basis despite informing them that my number is being used *****ulently. They confirmed that the name associated with my number (Lucky Modisane) which I have countlessly indicated is not me nor do I know who they are. I asked them to please remove my number from their system which they indicated they will but I am still being harassed with between 3-4 calls a day. I tried blocking all the numbers but they are relentless. What is the next step in reporting this harassment? Clearly the administrative processes to remove a number are poor or they just couldn't care!