Cartrack harassment in spite of them having the wrong number!

I have been harassed by Cartrack for months on end looking for a “Moyo” who owes them money. I have repeatedly told them they have the wrong number and time and again I am assured they will take my number off the system. After not getting any joy from my numerous requests, I contacted their client services via email on 26 April and they requested that I send my number so that it may be removed (no aplogies made). Of course this has not happened and I am still receiving up to 5 calls a day from them (blocking the numbers has not helped). If this is their level of incompetence in such a simple request, I wonder how they conduct the rest of their business.