Matric Vehicle Tracking's response to enquiries is non-existent

After 18 years with a tracker device in my car paying with debit order I decided to sell this car urgently, so I tried to contact them by phone, e-mail and whatsApp requesting detail of how to cancel the contract and where I must take the vehicle to get the device removed. since I have received no response on my e-mail or Whatsapp request. I made a call this morning at 09h15 to *** and selected option 5 then 3 the phone is now ringing for 21 minutes with no answer by a consultant then suddenly the call was disconnected. I THINK IT IS PATHETIC SERVICE AND WOULD NOT RECOMMEND THEM TO ANYONE