Wrong information

After several attempts and years passing I tried to remove my cellphone number from TEMP-CA225100's cartrack device as Florah Zameye Mzimela was the previous owner of my cellphone number. I spoke to one of Cartrack's operators who explained to me they can't remove my number as it is another entity that handles the smss going out. I am still receiving the smss of the test Cartrack does on Florah's vehicle and I need it to stop. Today I phone the Cartrack's call centre yet again and twice they cut the line while I was speaking. If Cartrack can't inform this entity that is assisting them how on earth will they get important info to Florah who's Cartrack device is linked to my phone???????????????