Tracker customer support is a joke. No feedback whatsoever

I have been been for tracker services for over 3 years on my Volvo but recently found out that the panic button is not been functioning for a while. I contacted tracker who sent through a technician. He found that the unit installed on my vehicle was faulty and replaced the whole unit. I was then sent an invoice of R550 for call out charge. I called a agent from Tracker and explained to her that when I did request someone to check my unit I was told if there was a problem on my end I will be charged the call out charge but if it was tracker then there will be no charge. I have told the agent to listen to the previous recordings and get back to me. Tracker said they will investigate and let me know if I must pay the charge but I have not heard anything back from them at all. Today I see the money was debited in full. How can you debit my account without providing proper feedback? Ridiculous