Disappointing Service from CarTrack‼️

I had an extremely disappointing service with CarTrack. I recently (beginning of March) found out that my tracker has not been updating any info for which i logged a call with CarTrack to investigate. Instead I was told I cannot be assisted unless I pay a call out fee for an engineer to come where I am to check the device, I then explained how that does not make sense that I have to pay for a call out fee when I do not know why my device stopped working. Out of dissatisfaction and disappointment with this service I canceled it and then again I was told I would be charged about 800+ Which I agreed. Now recently about 2 days ago I opened my app only to find that my tracker is now updating again. So what I need to understand exactly is what exactly was I supposed to pay the engineer for? Why could they not pick up on their side what the issue is cause now my device is working and no engineer has come to look at it? Also, if my device was able to go that long undetected exactly what recovery promise were they selling me exactly when I first took out the subscription? I’m very disappointed that I been a client for that long and this is the kind of service I received!