Short payment

The service is 0 zero i received a email mid December that i need to pay certain amount because December holidays, i did as they asked but two weeks later i received another email saying am short paid which i paid the amount i was asked to pay while I've been loyal to them for more than 2 years with more than 2 vehicle and they saying they take accountability but still i need to do they payment but from other means of communication they said my account is up to date after the payment cartracker is a Zero even consultant treat calls with emotions