Very poor service

My sold vehicle had a Matrix tracking device for the past 11 years and on numerous accounts I tried testing the device, with no luck or lack of assistance from Mix Telematics. For the past 2 years I was on a month-to-month contract and when I sold my vehicle last month, I tried to contact the cancellations department at Mix Telematics, but after 3 hours and 15 calls I gave up. I send an email to the cancellations department (and customer care) and received a reverence number. Today I received my Invoice for next month and emailed them back (no response) and again tried for 2 hours to talk to someone at cancellations or accounts or customer Services, but no one is answering the phone.... NOTHING ...NIKS ....LUTHO You can press "7" to leave a message for an agent to call you back - but the mailbox is full ..... With Mix Telematics refusing to call us back and reading all these very bad reviews on Hello Peter makes me thing we need a Mass/Class Action against Mix Telematics.