Defective tracking unit from matrix

I here write my poor heart regarding the poor service i received from matrix tracking device Apparently my kombi was missing together with the driver its by the grace of God his alive n the kombi is in tact Upon signing the deal i ws promised tha everywhere my kombi goes or starts I'll be alerted of the whereabout anywhere in africa To my suprise i have been paying the unit which is faulty and defective for the past 4 months When i tell them to stop withdrawing the money or else I'll reverse the money they told me they'll take me to ITC credit bureau How can i be assisted my matrix tracking company is taking my money for free because their unit is not working