Pathetic service and administration from Tracker

After reporting them a couple of weeks ago on hellopeter for not responding to a request to fixed a unit that did not operate for one single day after installation. I had to make use of an alternative service provider. The unit was also removed by Tracker and therefore cancelled all contractual comitments between us. I now have to struggle with threatening sms that my account is in arrears. At the call centre they advise me that their is a note on my account that the account is up to date but I am still receiving sms advising me differently.