Defective device

I’m so dissatisfied with the news I have received today from Cartrack. I have been a loyal customer ever since I bought my car in 2013. I have received an SMS late in September 2019 stating that my device needs maintenance and I should contact Cartrack for arrangements... I visited the Waterhlen branch in Pretoria to get the matter addressed..I was then put through to customer services where I was told that my device has issues with the GPS and sometimes doesn’t show the car movements...this basically means I haven’t in case of an emergency they can’t really find my car. what am I currently paying for? I was further informed that my warranty expired in 2016 and for them to repair the device I will have to pay R600.00. The consultant advised that the next option is to renew the contract, remove the old device then pay about R400 for new device. My premium will also increase from R120 to R200. And do remember the new contract is 3yrs binding. If is this how loyal customers are treated...then I have to say bye bye.