I had a fleet management unit installed on my car for 1 purpose only - convenience of logging business trips and not having to struggle when compiling petrol recons

I had a fleet management unit installed on my car for 1 purpose only - convenience of logging business trips and not having to struggle when compiling petrol recons. I recently discovered that the unit is not accurate by ****M +, I called CarTrack to either resolve this by reinstalling the unit or to cancel my contract. The agent said he’d reset it on his side. Last night, I checked my odometer reading and compared it to the reading am the app, and obviously app was more than on the odometer. I sent them a call back via website on Monday, it’s Wednesday today and no one has gotten back to me or acknowledged my email.