Usual bad service from Tracker

Every 6 months (for the past 18 months), my Tracker unit fails the test and every time a technician needs to be called out to test/repair the unit. I don't even get notified that the test has failed, but need to make a note in my diary to follow up myself every 6 months. I contacted the call centre on 2 November and was told that I would be contacted to make an appointment for a callout after the previous weeks test failed. As usual with Tracker, nothing has happened....Why does it always take several phone calls and a Hello Peter complaint to get things moving????