Poor service

Last year march 2020,i got a call from fidelity secure drive marketing about their car track device and how it work i was convinced and emmediately sign up telefonically and at the later stage i got a call from their installer who came after few days to install the device in my car,within a day or 2 i got an email from their track company stating the device is off as to how i dont know and even on my app it showed that is inactive,ive send an email back to them because the device was on and off as i monitor on my app and the worst part of it is that it couldnt last for a week of installation date,in few weeks trying to get their attention a lady phone me saying they will send an installer to come and check,the installer came and it started to show on my app again,then at night it was inactive again i got an emeil alert from technical site that the device is off again in less than 2 days and it was off ever since then,i made a phone call again wrote an email again i was told by the lady on the phone that the matter will be taken to technical department and will be resolved,months went by no body came back to me and now i get calls and emails from their debt collectors telling me to pay the some of two thousands that i owe fidelity,am very dissapointed at this as to who does that!! who runs such business that one sign up and pay no matter what the out come would be just pay and as for service forget but to collect the money,this is uncalled for!! am the one who should be taking further steps as they trying to **** money out of me knowingly that their services are poor. what if my car got ****** what would be their responce to me since their device is off whilst am thinking is active, people should be well aware off such kind of businesses and as cars get ****** and never recovered,thanks to their app as it showed no sign of the device and emails i got from them these 2 couldnt lie to me or **** me but showed well off even when am driving it couldnt show on the app ,because imagine if i didnt have this things i would be paying for something that is not there!!they should be ashamed for taking my name intrash spoiling my future and reputation i hate to think of my name being at credit bereau for some money that i dont owe to any one.pls fellow south Africans be sure of what we getting our selves into when approached by such kind of business or any other business's on things we dont understand or dont know how to track that they work or not.