Unreliable tracking company

I am so disappointed. I called cartrack on the 8th of May as I could not see location of my car. The app was reflecting 15 April 2020. Then they checked and assured me that all is fine. When I checked the next day I could see the location. Today I just decided to check and the last location was on the 9th of May and now when I call them they say my unit is faulty. On the 23th of April I received an sms saying my unit has been tested and it is working. So if I did not call them I wouldn't have known that I am at risk as I have a faulty tracker. This is not even the first time when I started with them I had the same problem where they always called me and said there is a power off signal which was not true. They had to replace the unit. This is just evidence that their units are unreliable. I would rather cancel and get a reliable tracking company than pay R600 for nothing and monthly installments as well.