I have 3 vehicles with Cartrack

I have 3 vehicles with Cartrack. Vehicle 1: They installed the unit in and did not put the correct mileage. I called via the call center for them to update. They said they updated but instead zeroed it. Vehicle 2: I requested an upgrade to fleet, I only got a response after a week. The person came to install but it’s more than 18 hours and I still cannot locate the vehicle on the app. I called him and he said I should drive around. Did that but still shows N/A Vehicle 3: This one has an SVR unit and I’m skeptical to upgrade it.